DIN EN ISO 7050 (DIN) and UNI 6955 (UNI) are equivalent fastener standards that specify the same or very similar products. Both standards cover 4 fastener types in our database.
DIN EN ISO 7050 (DIN standard) and UNI 6955 (UNI standard) are equivalent standards that define the same fastener geometry and mechanical requirements. Minor differences may exist in tolerances, marking requirements, or referenced test methods, but the products are interchangeable in most applications. Always verify specific project requirements with your engineer.
| Property | DIN EN ISO 7050 | UNI 6955 |
|---|---|---|
| Standard Body | DIN | UNI |
| Product Types | 4 fastener types | |
| Interchangeable? | Yes — equivalent standard | |
From: Cross Recessed Countersunk Head Tapping Screws — applies to both DIN EN ISO 7050 and UNI 6955
| Size | P | k_max | k_min | s_max | s_min | ds_max | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| ST2.2 | 1.1 | 2 | 3.5 | 5.5 | 5.2 | 0.91 | 1.7 | 1.43 |
| ST2.9 | 1.3 | 2 | 4.2 | 6.8 | 6.5 | 1.62 | 2.35 | 2.14 |
| ST3 | 1.34 |
Both DIN EN ISO 7050 and UNI 6955 fasteners are available with various surface treatments. Common options for these standards include:
Request detailed technical specifications, material certifications, and availability information for your application requirements. Our engineering team can provide product recommendations, custom specifications, and technical documentation.
| 2 |
| 4.6 |
| 7.3 |
| 7 |
| 2.03 |
| 2.5 |
| 2.53 |
| ST3.5 | 1.6 | 2 | 5.1 | 8.8 | 8.5 | 2.59 | 2.8 | 3.1 |
| ST3.9 | 1.8 | 3 | 6.8 | 10.7 | 10.3 | 2.95 | 3.2 | 3.53 |
| ST4.0 | 1.8 | 3 | 7.1 | 12.2 | 11.8 | 3.33 | 3.65 | 3.91 |
| ST4.2 | 2.1 | 3 | 7.8 | 14.2 | 13.9 | 4.96 | 4.65 | 4.36 |
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