Standard: BS 7670
Available sizes: M3 to M6 (4 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M3 | 0.7 | 0.55 | 0.65 | 6 | 4.2 | 1 | 0.6 | 5.895 | 9.83 | 6.18 | 5.97 |
| M4 | 1 | 0.6 | 0.75 | 8 | 6.3 | 1.12 | 0.68 |
| 7.87 |
| 12.02 |
| 8.22 |
| 7.96 |
| M5 | 1.5 | 1 | 1.15 | 12.5 | 10.5 | 1.55 | 0.95 | 12.34 | 18.74 | 12.77 | 12.45 |
| M6 | 1.75 | 1.2 | 1.4 | 14.8 | 12.6 | 1.55 | 0.95 | 14.64 | 20.91 | 15.07 | 14.75 |
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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