Standard: GB /T 925 - 1988
Available sizes: M4 to M6 (3 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M4 | 5.8 | 1 | 7.85 | 5.05 | 3.5 | 5.74 | 5.2 | 3.35 | 8 | 5.35 | 3.65 |
| M5 | 9 | 1.4 | 11.73 | 6.82 | 4.5 | 8.9 | 7 | 4.35 | 12 | 7.18 | 4.65 |
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.
| M6 |
| 11 |
| 1.4 |
| 13.73 |
| 7.82 |
| 5 |
| 10.9 |
| 8 |
| 4.85 |
| 14 |
| 8.18 |
| 5.15 |
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