Standard: BS 4464 - 1969
Available sizes: (M3.5) to M8 (7 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| (M3.5) | 4.35 | 0.15 | 1.4 | 0.9 | 4.1 | 1.5 | 0.8 | 7.55 | 1.6 | 1 |
| M10 | 23.3 | 0.4 | 5.8 | 4 | 22.4 | 6 | 3.8 | 35.7 | 6.2 | 4.2 |
| M12 | 25.3 | 0.5 |
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.
| 6.75 |
| 5 |
| 24.4 |
| 7 |
| 4.8 |
| 39.8 |
| 7.25 |
| 5.2 |
| M4 | 6.4 | 0.2 | 2.35 | 1.6 | 6.1 | 2.5 | 1.5 | 11.7 | 2.65 | 1.7 |
| M5 | 10.6 | 0.3 | 3.3 | 2.2 | 10.2 | 3.5 | 2.05 | 18.0 | 3.7 | 2.35 |
| M6 | 14.7 | 0.4 | 4.3 | 3 | 14.2 | 4.5 | 2.85 | 24.1 | 4.7 | 3.15 |
| M8 | 19 | 0.4 | 4.8 | 3.5 | 18.3 | 5 | 3.3 | 29.4 | 5.2 | 3.7 |
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