Standard: GB 1337 - 1988
Available sizes: M10 to M8 (7 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M10 | / | 32 | 12.28 | 20 | 20.26 | 1.5 | 23.7 | 12.5 | 12.72 | 23.6 | 19.74 |
| M12 | / | 36 | 13.78 | 22 | 22.26 | 1.5 | 25.7 | 14 | 14.22 | 25.6 | 21.74 |
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.
| M3 | 0.7 | 7 | 2.37 | 5 | 5.15 | / | 4.8 | 2.5 | 2.63 | 4.74 | 4.85 |
| M4 | 1 | 10 | 3.35 | 7 | 7.18 | / | 6.9 | 3.5 | 3.65 | 6.8 | 6.82 |
| M5 | 1.5 | 17 | 5.35 | 10 | 10.18 | / | 11 | 5.5 | 5.65 | 10.9 | 9.82 |
| M6 | / | 22 | 7.82 | 13 | 13.22 | 1.5 | 15.5 | 8 | 8.18 | 15.4 | 12.78 |
| M8 | / | 27 | 10.78 | 16.5 | 16.72 | 1.5 | 19.6 | 11 | 11.22 | 19.5 | 16.28 |
© 2026 Ningbo Ruixi Metal Surface Technology Co., Ltd.. All rights reserved.