SEMS Screws with Captive Spring Washer manufactured to DIN 6900-4 are dimensioned by the size table reproduced on this page. The standard fixes geometry and tolerances only; material and property class are assigned by ISO 898-1/898-2, and surface finish by separate finish standards.
DIN 6900-4 — Scope
DIN 6900-4 specifies the dimensions and tolerances of sems screws with captive spring washer. 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 6900-4, alongside the related DIN 6900-4 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 6900-4
| Thread size | Pitch (mm) | Head diameter dk (mm) | Head height k (mm) | Washer outer diameter (mm) | Cross recess | Common length range (mm) | Reference standard |
|---|---|---|---|---|---|---|---|
| M3 | 0.5 | 5.6 | 2.4 | 6.2 | PH1 / PZ1 | 5~30 | DIN 6900-4 |
| M4 | 0.7 | 8.0 | 3.1 | 8.0 | PH2 / PZ2 | 6~40 | DIN 6900-4 |
| M5 | 0.8 | 9.5 | 3.7 | 10.0 | PH2 / PZ2 | 8~50 | DIN 6900-4 |
| M6 | 1.0 | 12.0 | 4.6 | 12.2 | PH3 / PZ3 | 8~60 | DIN 6900-4 |
| M8 | 1.25 | 16.0 | 6.0 | 15.4 | PH4 / PZ4 | 10~60 | DIN 6900-4 |
| M10 | 1.5 | 20.0 | 7.5 | 18.4 | PH4 / PZ4 | 12~60 | DIN 6900-4 |
Equivalent Standards
Where direct equivalents exist (ISO ↔ DIN, ISO ↔ ASME), they are listed on the parent SEMS Screws with Captive Spring Washer page. Always confirm against the dimensions on this page, since some "equivalent" standards differ in tolerances and head geometry.
When to Specify DIN 6900-4
DIN 6900-4 is still widely used in European mechanical engineering and as a cross-reference on legacy drawings; its ISO equivalent is preferred for new designs.
