Standard: BS 7670
Available sizes: M4 to M8 (4 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M4 | 0.8 | 3.9 | 4.2 | 6 | 5.25 | 1.15 | 0.85 | 0.9 | 0.7 | 6.18 | 12 |
| M5 | 1.25 | 6.14 | 6.5 | 10 | 8.4 | 1.65 | 1.35 |
| 1.1 |
| 0.9 |
| 10.22 |
| 18 |
| M6 | — | 8.64 | 9 | 13.5 | 11.7 | 2.2 | 1.8 | 1.5 | 1.3 | 13.77 | 25 |
| M8 | 1.75 | 9.14 | 9.5 | 13.5 | 12.6 | 2.2 | 1.8 | 1.5 | 1.3 | 13.77 | 25 |
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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