Standard: GB 961 - 1988
Available sizes: 3 to 5 (3 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 3 | 21.5 | 0.494 | 0.329 | 7.64 | 5.16 | 22.02 | 20.98 | 3 | 2.75 | 8 | 5 |
| 4 | 23.5 | 0.565 | 0.404 | 9.64 | 7.2 | 24.02 | 22.98 | 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.
| 2.75 |
| 10 |
| 7 |
| 5 | 33.5 | 1.174 | 0.838 | 15.57 | 11.24 | 34.12 | 32.88 | 4 | 3.7 | 16 | 11 |
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