DIN 6888 (DIN) and UNI 6606 (UNI) are equivalent fastener standards that specify the same or very similar products. Both standards cover 4 fastener types in our database.
DIN 6888 (DIN standard) and UNI 6606 (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 6888 | UNI 6606 |
|---|---|---|
| Standard Body | DIN | UNI |
| Product Types | 4 fastener types | |
| Interchangeable? | Yes — equivalent standard | |
From: Drive Type Fastenings Without Taper Action, Woodruff Keys — applies to both DIN 6888 and UNI 6606
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| (2.5) | 3.97 | 15.72 | 2.4 | 6.5 | 6.35 | 16 |
| 1 | 1.475 | 6.76 | 0.153 | 2.6 | 2.5 | 7 |
| 1.5 | 1.975 | 9.66 | 0.414 | 3.7 | 3.58 | 10 |
| 2 |
Both DIN 6888 and UNI 6606 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.
| 2.975 |
| 15.72 |
| 1.8 |
| 6.5 |
| 6.35 |
| 16 |
| 3 | 4.97 | 15.72 | 3.01 | 6.5 | 6.35 | 16 |
© 2026 Ningbo Ruixi Metal Surface Technology Co., Ltd.. All rights reserved.