Standard: GB /T 6563 - 2014
Available sizes: M2 to M5 (5 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M2 | 0.45 | 1.1 | 0.1 | 0.1 | 5.45 | 1.35 | 25 | 1.825 | 1.575 | 0.25 | 1.7 |
| M2.5 | 0.7 | 1.75 | 0.2 | 0.15 | 7.66 | 2.1 | 38 | 2.925 |
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.
| 2.675 |
| 0.4 |
| 2.8 |
| M3 | 1 | 2.5 | 0.25 | 0.15 | 11.05 | 3 | 38 | 4.15 | 3.85 | 0.5 | 4 |
| M4 | 1.5 | 3.8 | 0.4 | 0.15 | 17.77 | 4.5 | 38 | 6.58 | 6.22 | 0.6 | 6.4 |
| M5 | 1.75 | 4.4 | 0.6 | 0.15 | 20.03 | 5.3 | 38 | 7.68 | 7.32 | 0.6 | 7.5 |
© 2026 Ningbo Ruixi Metal Surface Technology Co., Ltd.. All rights reserved.