Standard: GB 809 - 1988
Available sizes: M2 to M5 (5 sizes)
| Size | P | s_max | s_min |
|---|---|---|---|
| M2 | 4.5 | 4.32 | 3.5 |
| M2.5 | 6 | 5.82 | 5 |
| M3 | 10 | 9.78 | 9 |
| M4 | 15 | 14.73 | 13 |
| M5 | 18 | 17.73 | 16 |
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.
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