DIN 557 (DIN) and UNI 5597 (UNI) are equivalent fastener standards that specify the same or very similar products. Both standards cover 2 fastener types in our database.
DIN 557 (DIN standard) and UNI 5597 (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 557 | UNI 5597 |
|---|---|---|
| Standard Body | DIN | UNI |
| Product Types | 2 fastener types | |
| Interchangeable? | Yes — equivalent standard | |
From: Square Nuts. ISO Metric Coarse Thread. Finish c. Dadi Quadri Normali. Filettatura Metrica ISO a Passo Grosso. Categoria C. — applies to both DIN 557 and UNI 5597
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| M10 | 2 | 23.16 | 38.2 | l3 | 12.3 | 24 |
| M5 | 1 | 9.64 | 2.77 | 5 | 4.52 | 10 |
| M6 | 1.5 | 15.57 | 10.7 | 8 | 7.42 | 16 |
Both DIN 557 and UNI 5597 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.
| M8 |
| 1.75 |
| 17.57 |
| 16.3 |
| 10 |
| 9.42 |
| 18 |
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