ISO 3912 (ISO) 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.
ISO 3912 (ISO 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 | ISO 3912 | UNI 6606 |
|---|---|---|
| Standard Body | ISO | UNI |
| Product Types | 4 fastener types | |
| Interchangeable? | Yes — equivalent standard | |
From: Drive Type Fastenings Without Taper Action, Woodruff Keys — applies to both ISO 3912 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 ISO 3912 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 |
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