For neoprene washers, DIN 125 A is the governing document for the dimensions listed below. Mechanical and performance requirements for this part family are set by its own standards, not by the bolt and screw property-class documents.
DIN 125 A — Scope
DIN 125 A specifies the dimensional requirements for neoprene washers. Material, surface condition and any performance rating are set by separate documents specific to this part family — ISO 898-1 and ISO 898-2, which govern bolt and nut property classes, do not apply here.
Tolerance & Product Grades
Tolerances for neoprene washers are given as limits on the individual dimensions in the table rather than as a fastener product grade. Where a general-tolerance class is cited on the drawing instead, it applies to the dimensions not otherwise toleranced.
Dimensions Specified by DIN 125 A
| Thread size | Inner diameter d1 (mm) | Outer diameter d2 (mm) | Thickness s (mm) | Hardness (Shore A) | Temperature range (deg C) | Reference standard |
|---|---|---|---|---|---|---|
| M3 | 3.2 | 7 | 1.0 | 60 | -35 to +100 | DIN 125 A series |
| M4 | 4.3 | 9 | 1.5 | 60 | -35 to +100 | DIN 125 A series |
| M5 | 5.3 | 10 | 1.5 | 60 | -35 to +100 | DIN 125 A series |
| M6 | 6.4 | 12 | 2.0 | 60 | -35 to +100 | DIN 125 A series |
| M8 | 8.4 | 16 | 2.0 | 60 | -35 to +100 | DIN 125 A series |
| M10 | 10.5 | 20 | 3.0 | 60 | -35 to +100 | DIN 125 A series |
| M12 | 13 | 24 | 3.0 | 60 | -35 to +100 | DIN 125 A series |
| M16 | 17 | 30 | 3.0 | 60 | -35 to +100 | DIN 125 A series |
Equivalent Standards
Where direct equivalents exist (ISO ↔ DIN, ISO ↔ ASME), they are listed on the parent Neoprene Washers page. Always confirm against the dimensions on this page, since some "equivalent" standards differ in tolerances and head geometry.
When to Specify DIN 125 A
DIN 125 A is still widely used in European mechanical engineering and as a cross-reference on legacy drawings; its ISO equivalent is preferred for new designs.
