Standard: JIS B 1251
Available sizes: (Φ3.5) to Φ4 (6 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| (Φ3.5) | 6.5 | 12.2 | 3 | 6.1 | 2.7 | 1.5 |
| (Φ4.5) | 12.8 | 21.5 | 6 | 12.2 | 4.2 | 3 |
| Φ2 | 2.9 | 5.2 | 1.2 | 2.6 | 1 | 0.6 |
| Φ2.5 | 3.9 | 6.6 | 1.6 |
| 3.6 |
| 1.2 |
| 0.8 |
| Φ3 | 5 | 8.3 | 2.4 | 4.6 | 1.5 | 1.2 |
| Φ4 | 8.7 | 15.4 | 4 | 8.2 | 3.2 | 2 |
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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