Standard: ISO 7040 - 2025
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 | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|
| (M7) | 2 | 23.67 | 24 | 26.75 | 19.1 | 17.28 | 16 | 14.1 | 11.28 | 22.49 | 17.8 |
| M3 | 0.7 | 6.78 | 7 | 7.66 | 6.5 | 4.6 | 4 | 3.3 | 2.64 | 6.2 | 5.92 |
| M4 | 1 | 9.78 | 10 | 11.05 | 8 | 6.75 | 6 | 4.9 | 3.92 | 8.88 | 7.42 |
| M5 | 1.25 | 12.73 | 13 | 14.38 | 9.5 | 8.75 | 8 | 6.44 | 5.15 | 11.63 | 8.92 |
| M6 | 1.75 | 17.73 | 18 | 20.03 | 14.9 | 12.96 | 12 | 10.37 | 8.3 | 16.63 | 14.2 |
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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