U-537-700

(Cable top styles with a rounded skirt)
 
U-537
Manufacturer or Marking
No Name (USA)
P.P. Inc. (USA)

NOTE: in 2008 and older reference books, there was a U-537A. It was just a trimming variation of the U-537 so has been removed.
U-537
Size: 76mm X 73mm (3 x 2 ⅞)
Example in Photo: P.P. Inc. (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-540
Manufacturer or Marking
No Name (USA)
O-B (USA)

NOTE: In 2008 and older reference books, there was a U-540A listed. Listing are now part of U-540.
Size: 92mm X 101mm (3 x 4)
Variations: Click on the thumbnail above to see style variations
Variations: Tap on the thumbnail above to see style variations
To directly link to this image copy and paste below URL:
 
U-541
Manufacturer or Marking
No Name (Thomas) (USA)
Size: 95mm X 107mm (3 ¾ x 4 ¼)
Variations: Click on the thumbnail above to see style variations
Variations: Tap on the thumbnail above to see style variations
To directly link to this image copy and paste below URL:
 
U-542
Manufacturer or Marking
No Name (New Lexington, flat inner skirt) (USA)
U-542
Size: 88mm X 95mm (3 ½ x 3 ¾)
Example in Photo: No Name (New Lexington, flat inner skirt) (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-544
Manufacturer or Marking
No Name (Pittsburg) (USA)
Pinco (USA)
U-544
Size: 82mm X 82mm (3 ¼ x 3 ¼)
Example in Photo: No Name (Pittsburg) (USA)
Photo Credit: Ben Kirsten
To directly link to this image copy and paste below URL:
 
U-545
Manufacturer or Marking
No Name (Pittsburg) (USA)
U-545
Size: 85mm X 82mm (3 ⅜ x 3 ¼)
Example in Photo: No Name (Pittsburg) (USA)
Photo Credit: Ben Kirsten
To directly link to this image copy and paste below URL:
 
U-546
Manufacturer or Marking
No Name (New Lexington) (USA)
No Name (Pittsburg) (USA)
No Name (USA)

NOTE: In 2008 and older reference books, there was a U-548 listed. Listings are now part of U-546
U-546
Size: 85mm X 73mm (3 ⅜ x 2 ⅞)
Example in Photo: No Name (Pittsburg) (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-552
Manufacturer or Marking
No Name (New Lexington) (USA)
No Name (USA)
No Name (Thomas) (USA)
G.P.Co. (USA)
NEW LEXINGTON, O. (USA)
THOMAS (USA)
U-552
Size: 88mm X 92mm (3 ½ x 3 ⅝)
Example in Photo: No Name (Thomas) (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-553
Manufacturer or Marking
No Name (USA)
U-553
Size: 88mm X 88mm (3 ½ x 3 ½)
Example in Photo: No Name (USA)
Photo Credit: Unknown
To directly link to this image copy and paste below URL:
 
U-554
Manufacturer or Marking
No Name (USA)
U-554
Size: 88mm X 88mm (3 ½ x 3 ½)
Example in Photo: No Name (USA)
Photo Credit: James Lindsey
To directly link to this image copy and paste below URL:
 
U-556
Manufacturer or Marking
No Name (Fred Locke Attic Dig) (USA)
U-556
Size: 82mm X 76mm (3 ¼ x 3)
Example in Photo: No Name (Fred Locke Attic Dig) (USA)
Photo Credit: Ken Willick
To directly link to this image copy and paste below URL:
 
U-556A
Manufacturer or Marking
Fred Locke (Fred Locke Attic Dig) (USA)
U-556A
Size: 88mm X 636mm (3 ¼ x 2 ½)
Example in Photo: Fred Locke (Fred Locke Attic Dig) (USA)
Photo Credit: Ken Willick
To directly link to this image copy and paste below URL:
 
U-558
Manufacturer or Marking
No Name (USA)
U-558
Size: 88mm X 79mm (3 ½ x 3 ⅛)
Example in Photo: No Name (USA)
Photo Credit: Fred Collier
To directly link to this image copy and paste below URL:
 
U-559
Manufacturer or Marking
No Name (New Lexington) (USA)
No Name (Thomas) (USA)
No Name (Trenton) (USA)
U-559
Size: 88mm X 79mm (3 ½ x 3 ⅛)
Example in Photo: No Name (Trenton) (USA)
Photo Credit: Matt Grayson
To directly link to this image copy and paste below URL:
 
U-560
Manufacturer or Marking
No Name (Imperial) (USA)
No Name (Pittsburg) (USA)
No Name (USA)
Imperial Crown Logo (USA)
Imperial (No Logo) (USA)
U-560
Size: 88mm X 82mm (3 ½ x 3 ¼)
Example in Photo: No Name (Imperial) (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-562
Manufacturer or Marking
No Name (Akron H-P, Dry Process) (USA)
U-562
Size: 88mm X 69mm (3 ½ x 2 ¾)
Example in Photo: No Name (Akron H-P, Dry Process) (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-562A
Manufacturer or Marking
No Name (Akron H-P, Dry Process) (USA)
U-562A
Size: 88mm X 76mm (3 ½ x 3)
Example in Photo: No Name (Akron H-P, Dry Process) (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-563
Manufacturer or Marking
No Name (USA)
U-563
Size: 101mm X 82mm (4 x 3 ¼)
Example in Photo: No Name (USA)
Photo Credit: James Berg
To directly link to this image copy and paste below URL:
 
U-564
Manufacturer or Marking
No Name (New Lexington) (USA)

Note: Previously known as U-564A
U-564
Size: 76mm X 107mm (3 x 4 ¼)
Example in Photo: No Name (New Lexington) (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-564A
Note: Listings now part of U-564
 
U-565
Manufacturer or Marking
No Name (New Lexington) (USA)
No Name (Pittsburg) (USA)
No Name (USA)

NOTE: in 2008 and older reference books there was also listings for Macomb and No Name (Macomb). They are now U-565A as they have a different profile
U-565
Size: 107mm X 76mm (4 ¼ x 3)
Example in Photo: No Name (New Lexington) (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-565A
Manufacturer or Marking
No Name (Macomb) (USA)
MACOMB (Dry Process) (USA)
U-565A
Size: 107mm X 76mm (4 ¼ x 3)
Example in Photo: MACOMB (Dry Process) (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-568
Manufacturer or Marking
No Name (USA)
Pinco (USA)
U-568
Size: 117mm X 88mm (4 x 3 ½)
Example in Photo: No Name (USA)
Photo Credit: James Lindsey
To directly link to this image copy and paste below URL:
 
U-570
Manufacturer or Marking
No Name (Pittsburg) (USA)
No Name (Thomas) (USA)
THOMAS (USA)
U-570
Size: 114mm X 92mm (4 ½ x 3 ⅝)
Example in Photo: No Name (Pittsburg) (USA)
Photo Credit: Fred Collier
To directly link to this image copy and paste below URL:
 
U-570A
Manufacturer or Marking
THOMAS (USA)
No Name (Thomas) (USA)

NOTE: U-570A has a pointed cut out VS the standard one on U-570. Both were cataloged, which is why each as a U-Number.
U-570A
Size: 114mm X 92mm (4 ½ x 3 ⅝)
Example in Photo: No Name (Thomas) (USA)
Photo Credit: Fred Collier
To directly link to this image copy and paste below URL:
 
U-572
Manufacturer or Marking
No Name (Pinco) (USA)
Pinco (USA)
U-572
Size: 120mm X 92mm (4 ¾ x 3 ⅝)
Example in Photo: Pinco (USA)
Photo Credit: Fred Collier
To directly link to this image copy and paste below URL:
 
U-576
Manufacturer or Marking
No Name (Pittsburg) (USA)
U-576
Size: 117mm X 82mm (4 x 3 ¼)
Example in Photo: No Name (Pittsburg) (USA)
Photo Credit: Greg Hale
To directly link to this image copy and paste below URL:
 
U-577
Manufacturer or Marking
No Name (Pittsburg) (USA)

NOTE: This is a 2 part glaze weld
U-577
Size: 133mm X 95mm (5 ¼ x 3 ¾)
Example in Photo: No Name (Pittsburg) (USA)
Photo Credit: Charles Robinson
To directly link to this image copy and paste below URL:
 
U-579
Manufacturer or Marking
No Name (USA)
Locke (USA)
LOCRE (LOCKE Error) (USA)
U-579
Size: 177mm X 114mm (7 x 4 ½)
Example in Photo: No Name (USA)
Photo Credit: Robin Harrison
To directly link to this image copy and paste below URL:
 
U-581
Manufacturer or Marking
No Name (Lima) (USA)
No Name (Thomas, Dry Process) (USA)
No Name (Thomas) (USA)
Locke (USA)

NOTE: In 2008 and older reference books this was known as U-606A. All listings are now part of U-581 as 2 numbers where assigned to the same insulator.
U-581
Size: 82mm X 63mm (3 ¼ x 2 ½)
Example in Photo: No Name (Lima) (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-582
Manufacturer or Marking
No Name (Thomas) (USA)
U-582
Size: 76mm X 85mm (3 x 3 )
Example in Photo: No Name (Thomas) (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-583
Manufacturer or Marking
No Name (Thomas) (USA)
U-583
Size: 76mm X 85mm (3 x 3 )
Example in Photo: No Name (Thomas) (USA)
Photo Credit: Robin Harrison
To directly link to this image copy and paste below URL:
 
U-584
Manufacturer or Marking
No Name (Thomas) (USA)
U-584
Size: 79mm X 98mm (3 x 3 )
Example in Photo: No Name (Thomas) (USA)
Photo Credit: Robin Harrison
To directly link to this image copy and paste below URL:
 
U-584A
Manufacturer or Marking
No Name (Thomas) (USA)
U-584A
Size: 79mm X 98mm (3 x 3 ¾)
Example in Photo: No Name (Thomas) (USA)
Photo Credit: James Lindsey
To directly link to this image copy and paste below URL:
 
U-585
Manufacturer or Marking
No Name (Thomas) (USA)
U-585
Size: 82mm X 104mm (3 ¼ x 4 ⅛)
Example in Photo: No Name (Thomas)
Photo Credit: National Insulator association
To directly link to this image copy and paste below URL:
 
U-585A
Manufacturer or Marking
No Name (Thomas) (USA)
U-585A
Size: 82mm X 104mm (3 ¼ x 4 ⅛)
Example in Photo: No Name (Thomas)
Photo Credit: Robin Harrison
To directly link to this image copy and paste below URL:
 
U-585B
Manufacturer or Marking
No Name (Thomas) (USA)
U-585B
Size: 82mm X 104mm (3 ¼ x 4 ⅛)
Example in Photo: No Name (Thomas)
Photo Credit: Robin Harrison
To directly link to this image copy and paste below URL:
 
U-587
Manufacturer or Marking
Fred Locke (Glazeweld, Fred Locke Attic Dig) (USA)
U-587
Size: 95mm X 57mm X 92mm (3 ¾ x 2 ¼ x 3 ⅝)
Example in Photo: Fred Locke (Glazeweld, Fred Locke Attic Dig) (USA)
Photo Credit: Ken Willick
To directly link to this image copy and paste below URL:
 
U-588
Manufacturer or Marking
No Name (Thomas) (USA)
U-588
Size: 88mm X 98mm (3 ½ x 3 ⅞)
Example in Photo: No Name (Thomas)
Photo Credit: Robin Harrison
To directly link to this image copy and paste below URL:
 
U-591
Manufacturer or Marking
No Name (USA)
U-591
Size: 101mm X 120mm (4 x 4 ¾)
Example in Photo: No Name (USA)
Photo Credit: Robin Harrison
To directly link to this image copy and paste below URL:
 
U-595
Manufacturer or Marking
No Name (Thomas No. 3 Cable) (USA)
U-595
Size: 101mm X 120mm (4 x 4 ¾)
Example in Photo: No Name (Thomas No. 3 Cable) (USA)
Photo Credit: Robin Harrison
To directly link to this image copy and paste below URL:
 
U-596
Manufacturer or Marking
No Name (Thomas) (USA)
U-596
Size: 101mm X 104mm (4 x 4 ⅛)
Example in Photo: No Name (Thomas) (USA)
Photo Credit: Ben Kirsten
To directly link to this image copy and paste below URL:
 
U-596A
Manufacturer or Marking
No Name (USA)
No Name (New Lexington) (USA)
U-596A
Size: 107mm X 95mm (4 ¼ x 3 ¾)
Example in Photo: No Name (New Lexington) (USA)
Photo Credit: Dave Kingston
To directly link to this image copy and paste below URL:
 
U-597
Manufacturer or Marking
No Name (G.P. Co.) (USA)
G.P. Co. (USA)
U-597
Size: 82mm X 63mm (3 ¼ x 2 ½)
Example in Photo: G.P. Co. (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-598
Manufacturer or Marking
No Name (Pittsburg) (USA)
O-B (USA)
U-598
Size: 88mm X 69mm (3 ½ x 2 ¾)
Example in Photo: No Name (Pittsburg)
Photo Credit: Roger Ziesak
To directly link to this image copy and paste below URL:
 
U-599
Manufacturer or Marking
No Name (USA)
U-599
Size: 95mm X 76mm (3 ¾ x 3)
Example in Photo: No Name (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-599A
Manufacturer or Marking
No Name (USA)
No Name (Pittsburg) (USA)
U-599A
Size: 92mm X 76mm (3 x 3)
Example in Photo: No Name (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-599B
Manufacturer or Marking
No Name (Dry Process) (USA)
MACOMB (Dry Process) (USA)
U-599B
Size: 98mm X 85mm (3 x 3 )
Example in Photo: No Name (Dry Process) (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-600
Manufacturer or Marking
No Name (USA)
O-B (USA)
U-600
Size: 95mm X 76mm (3 ¾ x 3)
Example in Photo: No Name (USA)
Photo Credit: Mary Ann Pike
To directly link to this image copy and paste below URL:
 
U-600A
Manufacturer or Marking
No Name (Pittsburg) (USA)
Westinghouse (USA)
U-600A
Size: 95mm X 69mm (3 ¾ x 2 ¾)
Example in Photo: No Name (Pittsburg) (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-600B
Manufacturer or Marking
No Name (Akron H-P?, Dry Process ) (USA)
No Name (Trenton) (USA)
G.P.Co. (USA)
U-600B
Size: 95mm X 76mm (3 ¾ x 3)
Example in Photo: No Name (Trenton) (USA)
Photo Credit: Matt Grayson
To directly link to this image copy and paste below URL:
 
U-601
Manufacturer or Marking
CP (Canada)
No Name (CP) (Canada)
No Name (G.P.Co.) (USA)
G.P.Co. (USA)

NOTE: Canadian units are also known as U-2582 in the “Worldwide Porcelain Insulators Chart”
U-601
Size: 95mm X 76mm (3 ¾ x 3)
Example in Photo: No Name (G.P.Co.) (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-602
Manufacturer or Marking
No Name (USA)
U-602
Size: 95mm X 76mm (3 ½ x 3)
Example in Photo: No Name (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-603
Manufacturer or Marking
No Name (Pittsburg) (USA)
U-603
Size: 88mm X 69mm (3 ½ x 2 ¾)
Example in Photo: No Name (Pittsburg) (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-604
Manufacturer or Marking
No Name (G.P.Co.) (USA)
U-604
Size: 95mm X 73mm (3 ¾ x 2 )
Example in Photo: No Name (G.P.Co.) (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-605
Manufacturer or Marking
No Name (Lima or Locke) (USA)
LOCKE (USA)
U-605
Size: 76mm X 60mm (3 x 2 )
Example in Photo: No Name (Lima or Locke) (USA)
Photo Credit: Fred Collier
To directly link to this image copy and paste below URL:
 
U-606
Manufacturer or Marking
No Name (Lima) (USA)
No Name (New Lexington) (USA)
U-606
Size: 82mm X 63mm (3 ¼ x 2 ½)
Example in Photo: No Name (Lima) (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-606A
Manufacturer or Marking
No Name (Thomas)

NOTE: In 2008 and older reference books, there was a U-606B listed. Listing are now moved to U-606A.
U-606A
Size: 82mm X 73mm (3 ¼ x 2 )
Example in Photo: No Name (Thomas)
Photo Credit: Matt Grayson
To directly link to this image copy and paste below URL:
 
U-608
Manufacturer or Marking
No Name (USA)
No Name (Lima) (USA)
Locke USA)
O-B (USA)
U-608
Size: 88mm X 66mm (3 ½ x 2 ⅝)
Example in Photo: No Name (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-608A
Manufacturer or Marking
No Name (USA)
No Name (Fred Locke) (USA)
Fred Locke (USA)
O-B (USA)
U-608A
Size: 88mm X 66mm (3 ½ x 2 ⅝)
Example in Photo: Fred Locke (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-608B
Manufacturer or Marking
No Name (USA)
No Name (Lima) (USA)
U-608B
Size: 88mm X 66mm (3 ½ x 2 ⅝)
Example in Photo: No Name (Lima) (USA)
Photo Credit: Michele Kotlarsky
To directly link to this image copy and paste below URL:
 
U-610
Manufacturer or Marking
No Name (USA)
No Name (Trenton) (USA)
Size: 88mm X 66mm (3 ¾ x 3)
Variations: Click on the thumbnail above to see style variations
Variations: Tap on the thumbnail above to see style variations
To directly link to this image copy and paste below URL:
 
U-610A
Manufacturer or Marking
No Name (Lima) (USA)
No Name (USA)
C over I (Canada)
Locke (USA)
O-B (USA)
O-B (teat rest) (USA)
Triangle M (USA)

NOTE: C over I (Cent Mark) (Canada) Units should also have a U-Number in the “Worldwide Porcelain Insulators Chart” range as U-1-999 are US only styles. No “Worldwide Porcelain Insulators” U-Number is yet available for this unit.
U-610A
Size: 95mm X 76mm (3 ¾ x 3)
Example in Photo: O-B USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-611
Manufacturer or Marking
MP (USA)
G.P.Co. (USA)
U-611
Size: 95mm X 76mm (3 ¾ x 3)
Example in Photo: MP (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-611A
Manufacturer or Marking
No Name (USA)
No Name (Lima) (USA)
Fred Locke (USA)
U-611A
Size: 98mm X 76mm (3 x 3)
Example in Photo: Fred Locke (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-611B
Manufacturer or Marking
No Name (Akron H-P, Teat Rest, Dry Process) (USA)
O-B (USA)
U-611B
Size: 95mm X 82mm (3 ¾ x 3 ¼)
Example in Photo: No Name (Akron H-P, Teat Rest, Dry Process) (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-612
Manufacturer or Marking
No Name (USA)
U-612
Size: 95mm X 85mm (3 ¾ x 3 ⅜)
Example in Photo: No Name
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-612A
Manufacturer or Marking
No Name (Pittsburg) (USA)
No Nam (Akron H.P.) (USA)
No Name (USA)
U-612A
Size: 98mm X 85mm (3 x 3 ⅜)
Example in Photo: No Name (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-613
Manufacturer or Marking
No Name (Locke) (USA)
U-613
Size: 76mm X 69mm (4 x 2.75)
Example in Photo: No Name (Locke) (USA)
Photo Credit: Jeff Katchko
To directly link to this image copy and paste below URL:
 
U-614
Manufacturer or Marking
No Name (USA)
No Name (1 " Pinhole) (USA)
U-614
Size: 107mm X 79mm (4 ¼ x 3 ⅛)
Example in Photo: No Name (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-615
Manufacturer or Marking
No Name (USA)
U-615
Size: 114mm X 88mm (4 ½ x 3 ½)
Example in Photo: No Name (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-615A
Manufacturer or Marking
No Name (Thomas) (USA)
U-615A
Size: 117mm X 88mm (4 x 3 ½)
Example in Photo: No Name (Thomas) (USA)
Photo Credit: Bill Rohde
 
U-616
Manufacturer or Marking
No Name (Thomas) (USA)
U-616
Size: 111mm X 101mm (4 x 4)
Example in Photo: No Name (Thomas) (USA)
Photo Credit: Bill Rohde
To directly link to this image copy and paste below URL:
 
U-617
Manufacturer or Marking
No Name (Pittsburg) (USA)
No Name (USA)
Knox (USA)

NOTE: In 2008 and older reference books, there was U-618 and U-641A listed. Both listings are now part of U-617
U-617
Size: 114mm X 107mm (4 ½ x 4 ¼)
Example in Photo: No Name (USA)
Photo Credit: Robin Harrison
To directly link to this image copy and paste below URL:
 
U-619
Manufacturer or Marking
No Name (USA)
Triangle M (USA)
U-619
Size: 127mm X 104mm (5 x 4 ⅛)
Example in Photo: No Name (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-620
Manufacturer or Marking
No Name (USA)
U-620
Size: 127mm X 117mm (5 x 4 ⅝)
Example in Photo: No Name (USA)
Photo Credit: Robin Harrison
To directly link to this image copy and paste below URL:
 
U-620A
Manufacturer or Marking
No Name (Pittsburg) (USA)
No Name (USA)

NOTE: In 2008 and older reference books, there is a U-620B listed. It is now merged with U-620A as it is the same insulator.
U-620A
Size: 111mm X 104mm (4 x 4 ⅛)
Example in Photo: No Name (Pittsburg) (USA)
Photo Credit: Ken Willick
To directly link to this image copy and paste below URL:
 
U-620B
Manufacturer or Marking
No Name (Thomas, 2-Part glazewled) (USA)
THOMAS (2-Part glazewled) (USA)

NOTE: In 2008 and older reference books, there was a U-943 listed. Listing are now moved to U-620B. The old U-620B Listing moved to U-620A
U-620B
Size: 146mm X 121mm (5 ¾ x 4 ⅞)
Example in Photo: No Name (Thomas, 2-Part glazewled) (USA)
Photo Credit: Bill Rohde
To directly link to this image copy and paste below URL:
 
U-621
Manufacturer or Marking
No Name (USA)
No Name (Pittsburg Date Code) (USA)
U-621
Size: 171mm X 127mm (6 ¾ x 5)
Example in Photo: No Name (USA)
Photo Credit: Ben Kirsten
To directly link to this image copy and paste below URL:
 
U-622
Manufacturer or Marking
No Name (USA)
U-622
Size: 146mm X 98mm (5 ¾ x 3 ⅞)
Example in Photo: No Name (USA)
Photo Credit: James Lindsey
To directly link to this image copy and paste below URL:
 
U-623
Manufacturer or Marking
P.P. Inc (USA)
U-623
Size: 85mm X 76mm (3 x 3)
Example in Photo: P.P. Inc. (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-625
Manufacturer or Marking
Illinois (USA)
Illinois Map (USA)
No Name (USA)
No Name (Cook) (USA)
G.P.Co. (USA)
148 (USA)
O-B (USA)
Pinco (USA)
P.P. Inc. (USA)
Westinghouse (USA)

NOTE: In 2008 and older Reference books, There was a U-625B U-625C and U-625D, Thy are no longer U-Numbers. The listings for U-625B are now part of U-625A as they are the same insulator with minor variations in the manufacturing process. Same is true for the old U-624, it is now part of U-625

U-625 Units have smaller conductor groove and shorter neck U-625A Units have wider groove and longer neck
U-625
Size: 95mm X 82mm (3 ¾ x 3 ¼)
Example in Photo: Pinco (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-625A
Manufacturer or Marking
No Name (USA)
B166 (USA)
COOK (USA)
Illinois map (USA)
Locke (USA)
O-B (USA)
P.P. INC. (USA)
Westinghouse (USA)

NOTE: In 2008 and older Reference books, There was a U-625B U-625C and U-625D, Thy are no longer U-Numbers. The listings for U-625B are now part of U-625A as they are the same insulator with minor variations in the manufacturing process.

U-625 Units have smaller conductor groove and shorter neck U-625A Units have wider groove and longer neck
Size: 95mm X 82mm (3 ¾ x 3 ¼)
Variations: Click on the thumbnail above to see style variations
Variations: Tap on the thumbnail above to see style variations
To directly link to this image copy and paste below URL:
 
U-626
Manufacturer or Marking
No Name (USA)
PINCO (USA)
U-626
Size: 88mm X 63mm (3 ½ x 2 ½)
Example in Photo: No Name (USA)
Photo Credit: Matt Grayson
To directly link to this image copy and paste below URL:
 
U-627
Manufacturer or Marking
No Name (USA)
Hartford Faience (USA)
Hartford Faience (A106) (USA)
KNOX (USA)
LAPP (USA)
THOMAS (USA)

NOTE: In 2008 and older reference books, there was a U-627B and C listed. Listing are now moved to U-627.
U-627
Size: 95mm X 73mm (3 ¾ x 2 ⅞)
Example in Photo: Hartford Faience (USA)
Photo Credit: Steve Jones
To directly link to this image copy and paste below URL:
 
U-627A
Manufacturer or Marking
No Name (Lima) (USA)


NOTE: In 2008 and older reference books, there was a U-609A listed. Listing are now part of U-627A as it was the same insulator.
U-627A
Size: 95mm X 73mm (3 ¾ x 2 ⅞)
Example in Photo: No Name (Lima) (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-628
Manufacturer or Marking
No Name (USA)
Illinois map (USA)
O-B (USA)
Pinco (USA)
THOMAS (USA)
Triangle M (USA)
Westinghouse (USA)

NOTE: In 2008 and older reference books, there was a U-628A Listed, It is now part of U-628
Size: 95mm X 79mm (3 ¾ x 3 )
Variations: Click on the thumbnail above to see style variations
Variations: Tap on the thumbnail above to see style variations
To directly link to this image copy and paste below URL:
 
U-629
Manufacturer or Marking
No Name (USA)
Franklin Porcelain (USA)
Illinois (USA)
Locke (USA)
P.P. Inc (USA)
S (Thomas)
THOMAS (USA)
Victor Ins Inc (USA)
U-629
Size: 95mm X 82mm (3 ¾ x 3 ¼)
Example in Photo: Locke (USA)
Photo Credit: Fred Collier
To directly link to this image copy and paste below URL:
 
U-629A
Manufacturer or Marking
No Name (USA)
Franklin Porcelain (USA)
Illinois (USA)
Locke (USA)
P.P. Inc (USA)
S (Thomas)
THOMAS (USA)
Victor Ins Inc (USA)
U-629A
Size: 95mm X 85mm (3 ¾ x 3 )
Example in Photo: Locke (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-629B
Manufacturer or Marking
No Name (USA)
No Name (Thomas) (USA)
Thomas (USA)

Note: In 2008 and older reference books, this was know as U-629D. All listings are now part of U-629B
U-629B
Size: 98mm X 82mm ( 3 x 3 ¼)
Example in Photo: Thomas (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-629C
Manufacturer or Marking
No Name (USA)
Locke (USA)
O-B (USA)
Pinco (USA)
THOMAS (USA)
Victor Ins. Inc. (USA)
U-629C
Size: 95mm X 82mm (3 ¾ x 3 ¼)
Example in Photo: THOMAS (USA)
Photo Credit: Bob Berry
To directly link to this image copy and paste below URL:
 
U-629D
Manufacturer or Marking
Lapp (USA)
Locke (USA)

Note: In 2008 and older reference books, this was know as U-629E. All listings are now part of U-629D
U-629D
Size: 98mm X 85mm ( 3 x 3 )
Example in Photo: Lapp (USA)
Photo Credit: James Lindsey
To directly link to this image copy and paste below URL:
 
U-630
Manufacturer or Marking
No Name (USA)
Chance (USA)
Franklin Porcelain (USA)
Lapp (USA)
O-B (USA)
P.P. Inc (USA)
S (Thomas)
THOMAS (USA)
Victor Ins. Inc. (USA)

NOTE: In 2008 and older reference books, there was a U-630A. All listings are now part of U-630
U-630
Size: 95mm X 82mm (3 ¾ x 3 ¼)
Example in Photo: O-B (USA)
Photo Credit: Charles Robinson
To directly link to this image copy and paste below URL:
 
U-631
Manufacturer or Marking
No Name (USA)
Pinco (USA)

NOTE: In 2008 and older reference books, there was a U-561 listed. Listing are now part of U-631.
U-631
Size: 95mm X 76mm (3 ¾ x 3)
Example in Photo: Pinco (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-631A
Manufacturer or Marking
No Name (USA)
Findlay (USA)
U-631A
Size: 95mm X 76mm (3 ¾ x 3)
Example in Photo: Findlay (USA)
Photo Credit: Bill Ostrander
To directly link to this image copy and paste below URL:
 
U-632
Manufacturer or Marking
No Name (USA)
J-D (USA)
P.P. Inc (USA)
U-632
Size: 95mm X 88mm (3 ¾ x 3 ½)
Example in Photo: J-D (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-633
Manufacturer or Marking
Illinois (USA)
U-633
Size: 98mm X 85mm (3 x 3 )
Example in Photo: Illinois (USA)
Photo Credit: Fred Collier
To directly link to this image copy and paste below URL:
 
U-634
Manufacturer or Marking
CP (Canada)
ITE (USA)
Lapp (6188) (USA)

NOTE: In 2008 and older reference books, there was a U-634B listed. Listing are now part of U-634 and U-634A.

ALSO NOTE: CP (Canada) Units should also have a U-Number in the “Worldwide Porcelain Insulators Chart” range as U-1-999 are US only styles. No “Worldwide Porcelain Insulators” U-Number is yet available for this unit.
U-634
Size: 95mm X 82mm (3 ¾ x 3 ¼)
Example in Photo: Lapp (USA)
Photo Credit: Jim Frustieri
To directly link to this image copy and paste below URL:
 
U-634A
Manufacturer or Marking
ITE (USA)
Locke (USA)
O-B (USA)
THOMAS (USA)
Victor (USA)
Size: 95mm X 82mm (3 ¾ x 3 ¼)
Variations: Click on the thumbnail above to see style variations
Variations: Tap on the thumbnail above to see style variations
To directly link to this image copy and paste below URL:
 
U-635
Manufacturer or Marking
BBC (USA)
ITE (USA)
No Name (USA)
O-B (USA)
U-635
Size: 95mm X 85mm (3 ¾ x 3 ⅜)
Example in Photo: ITE (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-638
Manufacturer or Marking
No Name (Thomas) (USA)

NOTE: In 2008 and older reference books, there was a U-638B listed. Listing are now moved to U-638 for ones with Horizontal crown line and U-638A for ones with NO Horizontal crown line.
U-638
Note: 114mm X 85mm (4 ½ x 3 ½)
Example in Photo: No Name (Thomas) (USA)
Photo Credit: Ken Willick
To directly link to this image copy and paste below URL:
 
U-638A
Manufacturer or Marking
No Name (Thomas) (USA)

NOTE: In 2008 and older reference books, there was a U-638B listed. Listing are now moved to U-638 for ones with Horizontal crown line and U-638A for ones with NO Horizontal crown line.
Size: 114mm X 85mm (4 ½ x 3 )
Variations: Click on the thumbnail above to see style variations
Variations: Tap on the thumbnail above to see style variations
To directly link to this image copy and paste below URL:
 
U-639
Manufacturer or Marking
Fred Locke (USA)
U-639
Size: 107mm X 95mm (4 ¼ x 3 ¾)
Example in Photo: Fred Locke (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-641
Manufacturer or Marking
No Name (USA)
VICTOR R= ∞ (USA)
U-641
Size: 107mm X 79mm (4 ¼ x 3 )
Example in Photo: No Name (USA)
Photo Credit: Robin Harrison
To directly link to this image copy and paste below URL:
 
U-642
Manufacturer or Marking
No Name (USA)
Illinois (USA)
Locke (USA)
O-B (USA)
THOMAS (USA)
U-642
Size: 114mm X 88mm (4 ½ x 3 ½)
Example in Photo: No Name (USA)
Photo Credit: Fred Collier
To directly link to this image copy and paste below URL:
 
U-642A
Manufacturer or Marking
No Name (USA)
G.P. Co. (USA)
P.P. Inc. (USA)
U-642A
Size: 114mm X 88mm (4 ½ x 3 ½)
Example in Photo: G.P. Co. (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-642B
Manufacturer or Marking
No Name (USA)
U-642B
Size: 114mm X 88mm (4 ½ x 3 ½)
Example in Photo: No Name (USA)
Photo Credit: Charles Robinson
To directly link to this image copy and paste below URL:
 
U-643
Manufacturer or Marking
No Name (Lima) (USA)
U-643
Size: 107mm X 69mm (4 ¼ x 2 ¾)
Example in Photo: No Name (Lima) (USA)
Photo Credit: Ken Willick
To directly link to this image copy and paste below URL:
 
U-645
Manufacturer or Marking
Hartford Faience (A108) (USA)
Westinghouse (USA)
U-645
Size: 114mm X 88mm (4 ½ x 3 ½)
Example in Photo: Hartford Faience (A108) (USA)
Photo Credit: James Lindsey
To directly link to this image copy and paste below URL:
 
U-647
Manufacturer or Marking
Lapp (USA)
U-647
Size: 114mm X 88mm (4 ½ x 3 ½)
Example in Photo: Lapp (USA)
Photo Credit: Charles Robinson
To directly link to this image copy and paste below URL:
 
U-647A
Manufacturer or Marking
No Name (USA)
Lapp (USA)
O-B (USA)
Thomas (USA)
U-647A
Size: 114mm X 88mm (4 ½ x 3 ½)
Example in Photo: O-B
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-648
Manufacturer or Marking
No Name (Lima) (USA)
No Name (Pittsburg) (USA)
No Name (Fred Locke) (USA)
No Name (USA)
Fred Locke (USA)
LIMA, N.Y. (USA)
O-B (USA)
Triangle M (USA)
VICTOR (USA)
VICTOR R= ∞ (USA)
Size: 114mm X 104mm (4 ½ x 4 )
Variations: Click on the thumbnail above to see style variations
Variations: Tap on the thumbnail above to see style variations
To directly link to this image copy and paste below URL:
 
U-648A
Manufacturer or Marking
No Name (USA)
U-648A
Size: 114mm X 104mm (4 ½ x 4 ⅛)
Example in Photo: No Name (USA)
Photo Credit: James Lindsey
To directly link to this image copy and paste below URL:
 
U-649
Manufacturer or Marking
No Name (USA)
IEP (USA)
J-D (USA)
Line Material (USA)
Pinco (USA)
PP-KNOX (USA)
Westinghouse (USA)
U-649
Size: 95mm X 95mm (4 ¾ x 4 ¾)
Example in Photo: IEP (USA)
Photo Credit: Charles Robinson
To directly link to this image copy and paste below URL:
 
U-650
Manufacturer or Marking
No Name (USA)
LOCKE (USA)
O-B (IUSA)
THOMAS (USA)
U-650
Size: 95mm X 88mm (4 ¾ x 3 ½)
Example in Photo: No Name (USA)
Photo Credit: Greg Hale
To directly link to this image copy and paste below URL:
 
U-651
Manufacturer or Marking
Locke (9995) (USA)
LOCKE R= ∞ (USA)
P.P. Inc. (USA)
THOMAS (USA)
Westinghouse (USA)
U-651
Size: 95mm X 92mm (4 ¾ x 3 ⅝)
Example in Photo: Westinghouse (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-652
Manufacturer or Marking
No Name (USA)
General Electric (USA)
Joslyn (USA)
Locke (USA)
THOMAS (USA)
U-652
Size: 120mm X 95mm (4 ¾ x 3 ¾)
Example in Photo: Locke (USA)
Photo Credit: Matt Grayson
To directly link to this image copy and paste below URL:
 
U-653
Manufacturer or Marking
L6R / Joslyn (USA)
Knox (USA)
Pinco (USA)
P.P. Inc. (USA)
Victor Ins. Inc. (USA)
U-653
Size: 120mm X 95mm (4 ¾ x 3 ¾)
Example in Photo: Pinco (USA)
Photo Credit: Fred Collier
To directly link to this image copy and paste below URL:
 
U-654
Manufacturer or Marking
Line Material (USA)
U-654
Size: 120mm X 98mm (4 ¾ x 3 )
Example in Photo: Line Material (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-655
Manufacturer or Marking
No Name (USA)
Chance (USA)
Knox (USA)
Locke (USA)
O-B (USA)
THOMAS (USA)
U-655
Size: 117mm X 98mm (4 x 3 )
Example in Photo: O-B (USA)
Photo Credit: Mid Norris
To directly link to this image copy and paste below URL:
 
U-657
Manufacturer or Marking
Gould (USA)
ITE (USA)
JD 66 (Not J-D) (USA)
THOMAS (USA)
U-657
Size: 111mm X 95mm (4 ¾ x 3 ¾)
Example in Photo: JD 66 (Not J-D) (USA)
Photo Credit: National Insulator Association
To directly link to this image copy and paste below URL:
 
U-658
Manufacturer or Marking
O-B (USA)
U-658
Size: 111mm X 98mm (4 ¾ x 3 )
Example in Photo: O-B (USA)
Photo Credit: Connor Stoehr
To directly link to this image copy and paste below URL:
 
U-659
Manufacturer or Marking
No Name (USA)
P.P. Inc. (USA)
THOMAS (USA)
U-659
Size: 111mm X 95mm (4 ¾ x 3 ¾)
Example in Photo: No Name (USA)
Photo Credit: James Lindsey
To directly link to this image copy and paste below URL:
 
U-659A
Manufacturer or Marking
No Name (P.P., Aluminum Coated Top) (USA)
No Name (P.P., Copper Coated Top) (USA)
P.P. (Aluminum Coated Top) (USA)
U-659A
Size: 123mm X 104mm (4 x 4 )
Example in Photo: No Name (P.P., Aluminum Coated Top) (USA)
Photo Credit: Mid Norris
To directly link to this image copy and paste below URL:
 
U-660
Manufacturer or Marking
No Name (Lapp) (USA)
Lapp (USA)
Locke (USA)
O-B (USA)
THOMAS (USA)
U-660
Size: 120mm X 95mm (4 ¾ x 3 ¾)
Example in Photo: O-B
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-660A
Manufacturer or Marking
No Name (USA)
Knox (USA)
Line Material (USA)
Locke (USA)
McGraw Edison (USA)
O-B (USA)
Pinco (USA)
THOMAS (USA)
Victor Ins. Inc. (USA)
U-660A
Size: 120mm X 95mm (4 ¾ x 3 ¾)
Example in Photo: O-B (USA)
Photo Credit: Mid Norris
To directly link to this image copy and paste below URL:
 
U-661
Manufacturer or Marking
Chance (USA)
U-661
Size: 123mm X 107mm (4 x 4 ¼)
Example in Photo: Chance (USA)
Photo Credit: Ben Kirsten
To directly link to this image copy and paste below URL:
 
U-662
Manufacturer or Marking
No Name (Westinghouse) (USA)
B155 (Westinghouse) (USA)
B166 (Westinghouse) (USA)
Westinghouse (USA)

NOTE: In 2008 and older reference books, there was a U-662A listed. Listing are now part of U-662.
Size: 114mm X 101mm (4 ½ x 4)
Variations: Click on the thumbnail above to see style variations
Variations: Tap on the thumbnail above to see style variations
To directly link to this image copy and paste below URL:
 
U-663
Manufacturer or Marking
No Name (USA)
No Name (J-D) (USA)
Illinois Map (261) (USA)
Knox (USA)
Chance (USA)
J-D (USA)
O-B (USA)
P.P. Inc. (USA)
THOMAS (USA)
Victor Ins Inc. (USA)

NOTE: In 2008 and older reference books, there was a U-663A Listed. It has been merged with U-663 as it is the same insulator.
U-663
Size: 120mm X 95mm (4 ¾ x 3 ¾)
Example in Photo: THOMAS
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-664
Manufacturer or Marking
No Name (USA)
P.P. Inc. (USA)
Size: 120mm X 101mm (4 ¾ x 4)
Variations: Click on the thumbnail above to see style variations
Variations: Tap on the thumbnail above to see style variations
To directly link to this image copy and paste below URL:
 
U-665
Manufacturer or Marking
Chance (USA)
Knox (USA)
Locke (USA)
O-B (USA)
THOMAS (USA)
U-665
Size: 120mm X 101mm (4 ¾ x 4)
Example in Photo: Chance (USA)
Photo Credit: Fred Collier
To directly link to this image copy and paste below URL:
 
U-665A
Manufacturer or Marking
No Name (P.P. Inc.) (USA)
P.P. Inc. (USA)
Victor Ins. Inc. (USA)
U-665A
Size: 120mm X 104mm (4 ¾ x 4 ⅛)
Example in Photo: Chance (USA)
Photo Credit: Fred Collier
To directly link to this image copy and paste below URL:
 
U-666
Manufacturer or Marking
Chance (USA)
Line Material (USA)
O-B (USA)
PP-KNOX (USA)
THOMAS (USA)
U-666
Size: 120mm X 101mm (4 ¾ x 4)
Example in Photo: O-B (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-667
Manufacturer or Marking
No Name (USA)
No Name (Westinghouse) (USA)
Illinois Map (261) (USA)
Locke (USA)
LOCKE R= ∞ (USA)
Victor Ins. Inc. (USA)
Westinghouse (USA)
U-667
Size: 120mm X 101mm (4 ¾ x 4)
Example in Photo: No Name (Westinghouse) (USA)
Photo Credit: Mid Norris
To directly link to this image copy and paste below URL:
 
U-667A
Manufacturer or Marking
Locke (6512) (USA)
U-667A
Size: 120mm X 101mm (4 ¾ x 4)
Example in Photo: Locke (6512) (USA)
Photo Credit: James Lindsey
To directly link to this image copy and paste below URL:
 
U-668
Manufacturer or Marking
No Name (USA)
Knox (USA)
Locke (6512) (USA)
THOMAS (USA)
Victor Ins. Inc. (USA)
U-668
Size: 127mm X 95mm (5 x 3 ¾)
Example in Photo: Victor Ins. Inc. (USA)
Photo Credit: Robin Harrison
To directly link to this image copy and paste below URL:
 
U-669
Manufacturer or Marking
No Name (USA)
G.P.Co. (USA)
Locke (USA)
P.P. Inc. (USA)
VICTOR R= ∞ (USA)
Size: 127mm X 104mm (5 x 4 )
Variations: Click on the thumbnail above to see style variations
Variations: Tap on the thumbnail above to see style variations
To directly link to this image copy and paste below URL:
 
U-669A
Manufacturer or Marking
No Name (USA)
THOMAS (USA)
U-669A
Size: 133mm X 104mm (5 ¼ x 4 ⅛)
Example in Photo: No Name (USA)
Photo Credit: Robin Harrison
To directly link to this image copy and paste below URL:
 
U-669B
Manufacturer or Marking
No Name (New Lexington)
U-669B
Size: 130mm X 111mm (5 x 4 ⅜)
Example in Photo: No Name (New Lexington)
Photo Credit: Ken Willick
To directly link to this image copy and paste below URL:
 
U-669C
Manufacturer or Marking
Fred Locke (USA)
U-669C
Size: 127mm X 104mm (5 x 4 ⅛)
Example in Photo: Fred Locke (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-669D
Manufacturer or Marking
VICTOR (USA)
R=∞ (USA)

NOTE: The 2 known examples where found in Italy but have standard 1 inch (25mm) US threads
U-669D
Size: 126mm x 102mm (5 x 4)
Example in Photo: VICTOR (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-670
Manufacturer or Marking
No Name (USA)
Locke (USA)
LOCKE R= ∞
Victor Ins. Inc (USA)

NOTE: In 2008 and older reference books, there is a listing for U-670C and U-670D. They are now both part of U-670 as they where small improvements made to the style over the years.
U-670
Size: 139mm X 88mm (5 ½ x 3 ½)
Example in Photo: No Name (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-670A
Manufacturer or Marking
No Name (USA)
VICTOR (USA)
Fred Locke (USA)
Triangle M (USA)
VICTOR R = ∞
U-670A
Size: 120mm X 95mm (4 ¾ x 3 ¾)
Example in Photo: Fred Locke
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-670B
Manufacturer or Marking
Lapp (USA)
U-670B
Size: 139mm X 88mm (5 ½ x 3 ½)
Example in Photo: Lapp (USA)
Photo Credit: Fred Collier
To directly link to this image copy and paste below URL:
 
U-671
Manufacturer or Marking
No Name (USA)
No Name (Lima?) (USA)
No Name (Pittsburg) (USA)
THOMAS (USA)
Westinghouse (USA)

NOTE: In 2008 and older reference books, there was a U-671A (Westinghouse) It is listed with the U-671 as it was the same style.
U-671
Size: 139mm X 88mm (5 ½ x 3 ½)
Example in Photo: No Name (USA)
Photo Credit: Ben Kirsten
To directly link to this image copy and paste below URL:
 
U-671A
Manufacturer or Marking
No Name (USA)
Thomas (USA)

NOTE: In 2008 and older reference books, this was listed as U-671B. The old listing for U-671A was moved to U-671 so U-671B moved on to the open spot for U-671A
U-671A
Size: 136mm X 88mm (5 x 3 ½)
Example in Photo: Thomas (USA)
Photo Credit: Charles Robinson
To directly link to this image copy and paste below URL:
 
U-672
Manufacturer or Marking
No Name (Pittsburg) (USA)
U-672
Size: 139mm X 88mm (5 ½ x 3 ½)
Example in Photo: No Name (Pittsburg) (USA)
Photo Credit: Fred Collier
To directly link to this image copy and paste below URL:
 
U-673
Manufacturer or Marking
Westinghouse (USA)
No Name (J-D) (USA)
No Name (Pittsburg) (USA)

NOTE: In 2008 and older reference books, there was a U-674 listed. It is now part of the U-673 listing.
U-673
Size: 139mm X 95mm (5 ½ x 3 ¾)
Example in Photo: No Name (Pittsburg) (USA)
Photo Credit: Fred Collier
To directly link to this image copy and paste below URL:
 
U-675
Manufacturer or Marking
Fred Locke (2 Part Glazeweld) (USA)

NOTE: The difference between U-675 and U-675A is U-675 is a 2 part Glazeweld and U-675A in not.
U-675
Size: 139mm X 101mm (5 ½ x 4)
Example in Photo: Fred Locke (2 Part Glazeweld) (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-675A
Manufacturer or Marking
Fred Locke (USA)

NOTE: The difference between U-675 and U-675A is U-675 is a 2 part Glazeweld and U-675A in not.
U-675A
Size: 139mm X 92mm (5 ½ x 3 )
Example in Photo: Fred Locke (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-675B
Manufacturer or Marking
Fred Locke (USA)
Size: 165mm X 101mm (6 ½ x 4)
Variations: Click on the thumbnail above to see style variations
Variations: Tap on the thumbnail above to see style variations
To directly link to this image copy and paste below URL:
 
U-679
Manufacturer or Marking
No Name (USA)
O-B (USA)
P.P. Inc. (USA)
Westinghouse (USA)

NOTE: In 2008 and older reference books, there was a U-678 listed. Listings are now part of U-679
U-679
Size: 139mm X 101mm (5 ½ x 4)
Example in Photo: Westinghouse (USA)
Photo Credit: Fred Collier
To directly link to this image copy and paste below URL:
 
U-680
Manufacturer or Marking
No Name (USA)
Westinghouse (USA)
THOMAS (USA)
U-680
Size: 139mm X 101mm (5 ½ x 4)
Example in Photo: No Name (USA)
Photo Credit: James Lindsey
To directly link to this image copy and paste below URL:
 
U-680A
Manufacturer or Marking
No Name (Pittsburg) (USA)
JD (USA)
Westinghouse (USA)
U-680A
Size: 136mm X 95mm (5 x 3 ¾)
Example in Photo: No Name (Pittsburg) (USA)
Photo Credit: Mid Norris
To directly link to this image copy and paste below URL:
 
U-680B
Manufacturer or Marking
Findlay (196A) (USA)
U-680B
Size: 139mm X 101mm (5 ½ x 4)
Example in Photo: Findlay (196A) (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-680C
Manufacturer or Marking
No Name (USA)
Findlay (USA)
U-680C
Size: 136mm X 104mm (5 x 4 )
Example in Photo: No Name (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-681
Manufacturer or Marking
COOK (USA)
Illinois Map (226-227) (USA)
THOMAS (USA)
Triangle M (226-267) (USA)
U-681
Size: 139mm X 101mm (5 ½ x 4)
Example in Photo: COOK (USA)
Photo Credit: James Lindsey
To directly link to this image copy and paste below URL:
 
U-681A
Manufacturer or Marking
JD (USA)
U-681A
Size: 139mm X 101mm (5 ½ x 4)
Example in Photo: JD (USA)
Photo Credit: Fred Collier
To directly link to this image copy and paste below URL:
 
U-682
Manufacturer or Marking
No Name (USA)
No Name (Westinghouse) (USA)
J-D (USA)
O-B (USA)
LOCKE (USA)
THOMAS (USA)
Knox (USA)
PINCO (USA)
Victor Ins. Inc. (USA)
Westinghouse (USA)

NOTE: In 2008 and older reference books, there was a U-682A Listed. It is now part of the U-682 Listing. U-682A now is for a JD Unit.
U-682
Size: 139mm X 107mm (5 ½ x 4 ¼)
Example in Photo: LOCKE (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-682A
Manufacturer or Marking
J-D (USA)

NOTE: In 2008 and older reference books, there was a U-683A. All those listings are now part of U-682. The New U-683A is for JD unit.
U-682A
Size: 136mm X 95mm (5 x 3 ¾)
Example in Photo: J-D (USA)
Photo Credit: Charles Robinson
To directly link to this image copy and paste below URL:
 
U-683
Manufacturer or Marking
No Name (J-D) (USA)
COOK (USA)
J-D (USA)
Locke (USA)
U-683
Size: 139mm X 101mm (5 ½ x 4)
Example in Photo: No Name (J-D) (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-683A
Manufacturer or Marking
No Name (USA)
Knox (USA)
Locke (USA)
Pinco (USA)
U-683A
Size: 139mm X 101mm (5 ½ x 4)
Example in Photo: Pinco (USA)
Photo Credit: Fred Collier
To directly link to this image copy and paste below URL:
 
U-684
Manufacturer or Marking
GE 23530 NP-69 (USA)
Lapp (USA)
Locke (USA)
Pinco (USA)
THOMAS (USA)
U-684
Size: 139mm X 101mm (5 ½ x 4)
Example in Photo: GE 23530 NP-69 (USA)
Photo Credit: Fred Collier
To directly link to this image copy and paste below URL:
 
U-687
Manufacturer or Marking
No Name (USA)
No Name (JD) (USA)
J-D (USA)
JD 66 (not Jeffery Dewitt) (USA)

NOTE: In 2008 and older reference books, there was a U-687A listed. Listing are now part of U-687.
U-687
Size: 139mm X 101mm (5 ½ x 4)
Example in Photo: JD (USA)
Photo Credit: Fred Collier
To directly link to this image copy and paste below URL:
 
U-689
Manufacturer or Marking
No Name (USA)
VICTOR (USA)
VICTOR R= ∞ (USA)
U-689
Size: 161mm X 107mm (6 x 4 ¼)
Example in Photo: No Name (USA)
Photo Credit: Fred Collier
To directly link to this image copy and paste below URL:
 
U-689A
Manufacturer or Marking
No Name (Lima) (USA)
U-689A
Size: 168mm X 107mm (6 x 4 ¼)
Example in Photo: No Name (Lima) (USA)
Photo Credit: Ken Willick
To directly link to this image copy and paste below URL:
 
U-690
Manufacturer or Marking
No Name (USA)
No Name (Pittsburg) (USA)
Locke (USA)
LOCKE R = ∞ (USA)
THOMAS (USA)
Victor Ins. Inc. (USA)

NOTE: In 2008 and older guides, There was a U-690A, U-690B U-691 and U-692. All listings are now part of U-690
U-690
Size: 161mm X 107mm (6 x 4 ¼)
Example in Photo: No Name (USA)
Photo Credit: James Lindsey
To directly link to this image copy and paste below URL:
 
U-694
Manufacturer or Marking
No Name (USA)
No Name (THOMAS) (USA)
U-694
Size: 139mm X 101mm (5 ½ x 4)
Example in Photo: No Name (THOMAS) (USA)
Photo Credit: Shaun Kotlarsky
To directly link to this image copy and paste below URL:
 
U-695
Manufacturer or Marking
No Name (THOMAS) (USA)
U-695
Size: 177mm X 101mm (7 x 4)
Example in Photo: No Name (THOMAS) (USA)
Photo Credit: Michele Kotlarsky
To directly link to this image copy and paste below URL:
 
U-697
Manufacturer or Marking
No Name (Thomas) (USA)

NOTE: In 2008 and older reference books, there was a U-697A listed. Listing are now part of U-697.
U-697
Size: 168mm X 85mm 6 x 3 )
Example in Photo: No Name (Thomas) (USA)
Photo Credit: Bill Ostrander
To directly link to this image copy and paste below URL:
 
U-697A
Manufacturer or Marking
No Name (Lima) (USA)

NOTE: In 2008 and older reference books, there was a U-697B listed. Listing are now moved to U-697A.
U-697A
Size: 171mm X 82mm 6 ¾ x 3 ¼)
Example in Photo: No Name (Lima) (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-698
Manufacturer or Marking
No Name (USA)
U-698
Size: 184mm X 142mm 7 ¼ x 5 )
Example in Photo: No Name (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-698A
Manufacturer or Marking
No Name (Thomas) (USA)
U-698A
Size: 184mm X 142mm (7 ¼ x 5 )
Example in Photo: No Name (Thomas) (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL:
 
U-699
Manufacturer or Marking
VICTOR R = ∞ (USA)
U-699
Size: 152mm X 104mm (6 x 4 )
Example in Photo: VICTOR R = ∞ (USA)
Photo Credit: Elton Gish
To directly link to this image copy and paste below URL: