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 | 0.5 | 0.7 | 7.05 | 6.48 | 1.75 | 8.45 | 1.45 | 1.2 | 7.55 | 6 |
| M4 | 1 | 0.8 | 1 | 10.95 | 9.58 | 2.5 | 12.55 |
| 2.05 |
| 1.8 |
| 11.45 |
| 9 |
| M5 | 1.5 | 1.4 | 1.6 | 18.85 | 15.7 | 3.75 | 20.65 | 3.25 | 3 | 19.35 | 15 |
| M6 | 1.75 | 1.7 | 1.9 | 22.85 | 18.7 | 4.38 | 24.65 | 3.9 | 3.6 | 23.35 | 18 |
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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