DIN is the international standard for split cotter pin — iso / din (series 102). This page sets out what the standard governs, the size range it specifies, and the related standards you will see referenced in datasheets.
DIN — Scope
DIN specifies the dimensions and tolerances of split cotter pin — iso / din (series 102). Material, property class, surface finish and packaging are governed by separate documents in the same standards family (for example ISO 898-1 for the mechanical property classes of bolts and screws).
Tolerance & Product Grades
DIN, alongside the related ISO / DIN entries on this site, specifies product grades (typically A or B for fine work and C for general engineering) and tolerance classes for the controlling dimensions. Choose the grade against the precision your application requires.
Dimensions Specified by DIN
| Nominal diameter (mm) | Length L (mm) | Material | Reference standard |
|---|---|---|---|
| 1.0 | 16 | Carbon steel | ISO 1234 / GB/T 91 |
| 1.2 | 20 | Carbon steel | ISO 1234 / GB/T 91 |
| 1.6 | 25 | Carbon steel | ISO 1234 / GB/T 91 |
| 2.0 | 32 | Carbon steel | ISO 1234 / GB/T 91 |
| 2.5 | 40 | Carbon steel | ISO 1234 / GB/T 91 |
| 3.2 | 50 | Carbon steel | ISO 1234 / GB/T 91 |
| 4.0 | 63 | Carbon steel | ISO 1234 / GB/T 91 |
| 5.0 | 80 | Carbon steel | ISO 1234 / GB/T 91 |
| 6.3 | 100 | Carbon steel | ISO 1234 / GB/T 91 |
| 8.0 | 125 | Carbon steel | ISO 1234 / GB/T 91 |
Companion Standards
DIN controls only the geometry of split cotter pin — iso / din (series 102). The mechanical strength is set by ISO 898-1 (bolts and screws) or ISO 898-2 (nuts); the surface finish is governed by separate finish standards (e.g. ISO 4042 for electroplating). For corrosion testing, the relevant document is ISO 9227 (neutral salt spray).
When to Specify DIN
DIN is still widely used in European mechanical engineering and as a cross-reference on legacy drawings; its ISO equivalent is preferred for new designs.