Standard: BS 3692 - 2001
Available sizes: M1.6 to M8 (8 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| M1.6 | 0.4 | 3.88 | 1.525 | 2 | 1.86 | 4 | 1.275 |
| M2 | 0.5 | 5.38 | 2.125 | 3 | 2.86 | 5.5 | 1.875 |
| M2.5 | 0.8 | 7.85 | 3.65 | 5 | 4.82 | 8 | 3.35 |
| M3 | 1.25 | 12.73 | 5.65 |
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.
| 8 |
| 7.78 |
| 13 |
| 5.35 |
| M4 | 1.75 | 18.67 | 8.18 | 12 | 11.73 | 19 | 7.82 |
| M5 | 2 | 23.67 | 10.18 | 16 | 15.73 | 24 | 9.82 |
| M6 | 2.5 | 29.67 | 13.215 | 20 | 19.67 | 30 | 12.785 |
| M8 | 2.5 | 31.61 | 14.215 | 22 | 21.67 | 32 | 13.785 |
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