Standard: BS 7644
Available sizes: M12 to M24 (5 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| M12 | 16.1 | 3.1 | 4.6 | 16.35 | 27.7 | 29 |
| M16 | 22.3 | 3.1 | 4.6 | 22.6 | 37.4 | 39 |
| M20 | 27.2 | 3.4 | 4.6 | 27.55 | 45.4 | 47 |
| M22 | 33.2 | 3.4 | 4.6 | 33.55 |
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.
| 54.1 |
| 56 |
| M24 | 36.2 | 3.4 | 4.6 | 36.55 | 60.1 | 62 |
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