Standard: BS 4320
Available sizes: (M14) to M8 (8 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| (M14) | 25 | 50 | 49.2 | 25.5 | 25 | 2.7 | 2.3 | 50 | 2.5 |
| (M18) | 37 | 72 | 71 | 37.6 | 37 | 3.3 | 2.7 | 72 | 3 |
| M10 |
| 17 |
| 34 |
| 33.2 |
| 17.4 |
| 17.0 |
| 2.2 |
| 1.8 |
| 34 |
| 2 |
| M12 | 21 | 39 | 38.2 | 21.5 | 21 | 2.2 | 1.8 | 39 | 2 |
| M16 | 31 | 60 | 59 | 31.6 | 31 | 2.7 | 2.3 | 60 | 2.5 |
| M20 | 40 | 77 | 76 | 40.6 | 40 | 3.3 | 2.7 | 77 | 3 |
| M6 | 8.4 | 21 | 20.5 | 8.7 | 8.4 | 1.1 | 0.9 | 21 | 1 |
| M8 | 13 | 28 | 27.5 | 13.4 | 13.0 | 1.8 | 1.4 | 28 | 1.6 |
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.
© 2026 Ningbo Ruixi Metal Surface Technology Co., Ltd.. All rights reserved.