ISO 4032 (ISO) and UNI 5588 (UNI) are equivalent fastener standards that specify the same or very similar products. Both standards cover 10 fastener types in our database.
ISO 4032 (ISO standard) and UNI 5588 (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 4032 | UNI 5588 |
|---|---|---|
| Standard Body | ISO | UNI |
| Product Types | 10 fastener types | |
| Interchangeable? | Yes — equivalent standard | |
From: Hexagon Nuts, Style 1 — applies to both ISO 4032 and UNI 5588
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (M3.5) | 1.5 | 16 | 6.4 | 10.00 | 14.6 | 0.6 | 0.15 | 8.4 | 8.04 | 10.80 | 17.77 |
| M1.6 | 0.4 | 4 | 1.1 | 2.00 | 3.1 |
Both ISO 4032 and UNI 5588 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.
| ✓ |
| Hexagon Regular Nuts, Style 1 - Product Grades A and B | ✓ |
| Metric Hexagon Nuts | ✓ |
| Hexagon Regular Nuts(Style 1) - Product Grades A and B | ✓ |
| 0.2 |
| 0.1 |
| 1.6 |
| 1.35 |
| 2.30 |
| 4.32 |
| M2 | 0.5 | 5.5 | 1.7 | 3.00 | 4.6 | 0.4 | 0.15 | 2.4 | 2.15 | 3.45 | 6.01 |
| M2.5 | 0.7 | 7 | 2.3 | 4.00 | 5.9 | 0.4 | 0.15 | 3.2 | 2.9 | 4.60 | 7.66 |
| M3 | 1 | 10 | 3.9 | 6.00 | 8.9 | 0.5 | 0.15 | 5.2 | 4.9 | 6.75 | 11.05 |
| M4 | 2 | 21 | 9.70 | 14.00 | 19.60 | 0.6 | 0.15 | 12.8 | 12.1 | 15.10 | 23.36 |
| M5 | 2.5 | 27 | 12.10 | 18.00 | 24.90 | 0.8 | 0.2 | 15.8 | 15.1 | 19.50 | 29.56 |
| M6 | 2.5 | 30 | 13.5 | 20.00 | 27.7 | 0.8 | 0.2 | 18 | 16.9 | 21.60 | 32.95 |
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