Standard: GB 39 - 1988
Available sizes: M10 to M8 (7 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| M10 | 2.5 | 16.2 | 42.9 | 34 | 33 | 18 | 89.57 |
| M12 | 3 | 16.9 | 45.5 | 36 | 35 | 19 | 101.9 |
| M3 | 0.7 | 2 | 8.63 | 7 | 6.64 | 3.2 | 0.49 |
| M4 | 1 | 3.8 | 12.53 |
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.
| 10 |
| 9.64 |
| 5 |
| 1.92 |
| M5 | 1.5 | 6.5 | 20.24 | 16 | 15.57 | 8 | 8.31 |
| M6 | 2 | 9.2 | 26.21 | 21 | 20.16 | 11 | 18.12 |
| M8 | 2.5 | 13.2 | 34.01 | 27 | 26.16 | 15 | 44.26 |
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