Standard: GB /T 902.4
Available sizes: M3 to M4 (2 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 902.4(IS) |
| ISO | ISO 13918(IS) |
| Size | P | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| M3 | 0.7 | 6.1 | 5.9 | 5/6 | 7.2 | 0.7 | 7° | 6.8 | 1.4 |
| M4 | 1 | 8.1 | 7.9 | 10 | 9.2 | 0.8 | 7° | 8.8 | 1.4 |
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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