DIN EN 1661 (DIN) and ISO 4161 (ISO) are equivalent fastener standards that specify the same or very similar products. Both standards cover 7 fastener types in our database.
DIN EN 1661 (DIN standard) and ISO 4161 (ISO 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 1661 | ISO 4161 |
|---|---|---|
| Standard Body | DIN | ISO |
| Product Types | 7 fastener types | |
| Interchangeable? | Yes — equivalent standard | |
From: Hexagon Nuts with Flange — applies to both DIN EN 1661 and ISO 4161
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| M10 | 2.5 | 29.16 | 42.8 | 20.0 | 18.7 | 30.00 | 32.95 |
| M5 | 1 | 9.78 | 14.2 | 6.0 | 5.7 | 10.00 | 11.05 |
| M6 | 1.5 | 15.73 | 21.8 | 10.00 | 9.64 |
Both DIN EN 1661 and ISO 4161 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.
| ✓ |
| 16.00 |
| 17.77 |
| M8 | 2 | 20.67 | 29.9 | 14.00 | 13.3 | 21.00 | 23.36 |
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