Standard: UNI 7473 - 1975
Available sizes: (M7) to M6 (5 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 889.1 |
| NF | NF E 25-409 |
| DIN | DIN EN ISO 7040 |
| ISO | ISO 7040 |
| UNI | UNI 7473 |
| Size | P | k_max | k_min | s_max | s_min | ds_max | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| (M7) | 2 | 12.8 |
| 24 |
| 1.5 |
| 26.75 |
| 37 |
| 18 |
| 37.7 |
| M3 | 0.7 | 3.2 | 7 | — | 7.74 | — | 6 | 1.05 |
| M4 | 1 | 4.8 | 10 | — | 11.05 | — | 7.8 | 2.92 |
| M5 | 1.25 | 6.4 | 13 | 1 | 14.38 | 6.23 | 10.6 | 6.33 |
| M6 | 1.75 | 9.6 | 19 | 1.25 | 21.1 | 18.9 | 14.8 | 19.3 |
Standard corrosion protection for indoor and mild outdoor environments.
Salt spray: 96–200 hours | RoHS compliant (trivalent chromium)
High-performance coating for automotive, marine, and harsh environments.
Salt spray: 720–1500 hours | Recommended for grade 8.8+
Heavy-duty protection for structural and outdoor applications.
Salt spray: 500–1000 hours | Thread tolerance adjustment required
Note for high-strength fasteners (Grade 10.9, 12.9): Electroplating processes require hydrogen embrittlement relief baking (minimum 4 hours at 200°C within 4 hours of plating). Contact our engineering team for grade-specific plating recommendations.
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.
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