Standard: GB /T 4388 - 2008
Available sizes: (10) to 8 (7 sizes)
| Size | P | s_max | s_min | k_nominal |
|---|---|---|---|---|
| (10) | 13 | 15 | 10 | 129 |
| (6) | 7 | 8 | 7 | 81 |
| (8) | 10 | 11 | 8.5 | 105 |
| (9) | 12 | 13 | 9.5 | 121 |
| 10 | 13 | 14 | 9.5 | 129 |
| 7 | 8 | 10 | 8 | 89 |
| 8 |
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.
| 10 |
| 13 |
| 9.5 |
| 105 |
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