Standard: GB /T 17880.3 - 1999
Available sizes: M3 to M8 (5 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M3 | 0.7 | 6.15 | 6 | 4.8 | 4.92 | 6 | 5.97 | 0.5 | 0.2 | 5.9 | 6.75 |
| M4 | 1 | 9.15 | 9 | 7.5 | 7.65 | 9 | 8.97 | 0.6 |
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.
| 0.2 |
| 8.9 |
| 10 |
| M5 | 1.5 | 13.15 | 13 | 11 | 11.18 | 13 | 12.97 | 0.85 | 0.3 | 12.9 | 14.5 |
| M6 | 1.75 | 15.15 | 15 | 13 | 13.18 | 15 | 14.97 | 0.85 | 0.3 | 14.9 | 16.5 |
| M8 | 1.5 | 15.15 | 15 | 13 | 13.18 | 15 | 14.97 | 0.85 | 0.3 | 14.9 | 16.5 |
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