Standard: GB 855 - 1988
Available sizes: M2.5 to M6 (5 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M2.5 | 3.5 | 4 | 5.24 | 12 | 11.65 | 3.2 | 5 | 5 | 4.76 | 4.7 | 12.35 |
| M3 | 5.6 | 6 | 8.29 | 16 | 15.65 | 5.3 | 9 | 8 | 7.71 | 8.64 | 16.35 |
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 |
| 8.76 |
| 8 |
| 11.35 |
| 20 |
| 19.58 |
| 8.4 |
| 14 |
| 11 |
| 10.65 |
| 13.57 |
| 20.42 |
| M5 | 13.43 | 12 | 16.35 | 28 | 27.58 | 13 | 22 | 16 | 15.65 | 21.48 | 28.42 |
| M6 | 17.43 | 15 | 20.42 | 32 | 31.5 | 17 | 27 | 20 | 19.58 | 26.48 | 32.5 |
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