Next: Washers Forms E and F 
Prev: Toothed Washers 
Washer forms run from A to F, where the form type refers to the outside diameter and thickness of the flat washers.
BS4320 washer forms A to D are typically supplied self-finish in a range of metals including steel alloys, brass and copper.
Form A washers: Normal diameter, normal thickness
Form B washers: Normal diameter, light thickness
Form C washers: Large diameter, normal thickness
Form D washers: Large diameter, light thickness
Available from stock with specials made to order.
We also supply washer forms E & F.
| SIZE | FORM A | FORM B | FORM C | FORM D | ||||
| OUTSIDE DIA | THICKNESS | OUTSIDE DIA | THICKNESS | OUTSIDE DIA | THICKNESS | OUTSIDE DIA | THICKNESS | |
| M2 | 5.0 | 0.3 | – | – | – | – | – | – |
| M2.5 | 6.5 | 0.5 | – | – | – | – | – | – |
| M3 | 7.0 | 0.5 | – | – | – | – | – | – |
| M4 | 9.0 | 0.8 | – | – | 10.0 | 0.8 | – | – |
| M5 | 10.0 | 1.0 | 12.5 | 0.8 | 12.5 | 1.0 | – | – |
| M6 | 12.5 | 1.6 | 12.5 | 0.8 | 14 | 1.6 | 14 | 0.8 |
| M8 | 17 | 1.6 | 17 | 1.0 | 21 | 1.6 | 21 | 1.0 |
| M10 | 21 | 2.0 | 21 | 1.25 | 24 | 2.0 | 24 | 1.25 |
| M12 | 24 | 2.5 | 24 | 1.6 | 28 | 2.5 | 28 | 1.6 |
| M14 | 28 | 2.5 | 28 | 1.6 | 30 | 2.5 | 30 | 1.6 |
| M16 | 30 | 3.0 | 30 | 2.0 | 34 | 3.0 | 34 | 2.0 |
| M18 | 34 | 3.0 | 34 | 2.0 | 37 | 3.0 | 37 | 2.0 |
| M20 | 37 | 3.0 | 37 | 2.0 | 39 | 3.0 | 39 | 2.0 |
| M22 | 39 | 3.0 | 39 | 2.0 | – | – | – | – |
| M24 | 44 | 4.0 | 44 | 2.5 | 50 | 4.0 | 50 | 2.5 |
| M27 | 50 | 4.0 | 50 | 2.5 | – | – | – | – |
| M30 | 56 | 4.0 | 56 | 2.5 | – | – | – | – |
| M33 | 60 | 5.0 | 60 | 3.0 | – | – | – | – |
| M36 | 66 | 5.0 | 66 | 3.0 | – | – | – | – |
| M39 | 72 | 6.0 | 72 | 3.0 | – | – | – | – |
