Standard: GB /T 899 - 1988
Available sizes: M2 to M6 (6 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| M2 | 0.45 | 2.9 | 4.1 | / | / | 2.25 | 3.5 | 2.5 |
| M2.5 | 0.7 | 5.4 | 6.6 | / | / | 3.7 | 6 | 4 |
| M3 | 1 | 9.25 | 10.75 | / | / | 5.7 | 10 | 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.
| M4 |
| 1.5 |
| 14.1 |
| 15.9 |
| 1.25 |
| 1 |
| 9.64 |
| 15 |
| 10 |
| M5 | 2 | 19.95 | 22.05 | 1.5 | / | 13.57 | 21 | 14 |
| M6 | 2 | 22.95 | 25.05 | 1.5 | / | 15.57 | 24 | 16 |
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