Standard: JIS B 1251
Available sizes: (3.5) to 4 (5 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| (3.5) | 6.7 | 0.6 | 0.64 | 6.4 | 11 | 1.2 | 9 | 10.5 | 0.56 |
| 2 | 2.9 | 0.3 | 0.325 | 2.7 | 5.7 | 0.6 | 7 | 5.4 | 0.275 |
| 2.5 |
| 3.9 |
| 0.45 |
| 0.485 |
| 3.7 |
| 7.5 |
| 0.9 |
| 8 |
| 7.1 |
| 0.415 |
| 3 | 5 | 0.5 | 0.535 | 4.8 | 9.5 | 1 | 8 | 9.1 | 0.465 |
| 4 | 7.7 | 0.8 | 0.85 | 7.4 | 13 | 1.6 | 9 | 12.5 | 0.75 |
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.
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