Standard: BS 4320
Available sizes: M10 to M8 (5 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| M10 | 19 | 37 | 36.2 | 19.5 | 19.0 | 3.3 | 2.7 | 37 | 3.0 |
| M4 | 5.3 | 12.5 | 12.1 | 5.5 | 5.3 | 1.1 | 0.9 | 12.5 | 1.0 |
| M5 |
| 8.4 |
| 21 |
| 20.5 |
| 8.7 |
| 8.4 |
| 1.8 |
| 1.4 |
| 21 |
| 1.6 |
| M6 | 13 | 28 | 27.5 | 13.4 | 13.0 | 2.7 | 2.3 | 28 | 2.5 |
| M8 | 17 | 34 | 33.2 | 17.4 | 17.0 | 3.3 | 2.7 | 34 | 3.0 |
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.