Standard: GB 808 - 1988
Available sizes: M4 to M8 (4 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| M4 | 8.79 | 7.78 | 0.33 | 1.7 | 1.3 | 8 |
| M5 | 13.25 | 11.73 | 1.45 | 3 | 2.6 | 12 |
| M6 | 15.51 | 13.73 | 1.78 | 3 | 2.6 | 14 |
| M8 | 18.9 | 16.73 | 2.65 | 3 |
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.
| 2.6 |
| 17 |
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