Standard: JIS B 2804
Available sizes: 3 to 9 (7 sizes)
| Standard Body | Standard Number |
|---|---|
| DIN | DIN 471(-2) |
| UNI | UNI 7435 |
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 3 | 3.7 | 0.22 | 0.255 | 0.35 | 1 | 3.74 | 3.55 | 1 | / | 0.4 | 5 |
| 4 | 5.6 | 0.33 | 0.37 | 0.55 | 1.2 | 5.64 | 5.45 | 1.2 |
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.
| / |
| 0.6 |
| 7.6 |
| 5 | 7.4 | 0.33 | 0.37 | 0.73 | 1.2 | 7.46 | 7.22 | 1.2 | / | 0.8 | 9.38 |
| 6 | 9.3 | 0.36 | 0.4 | 0.91 | 1.5 | 9.4 | 8.94 | 2 | 6 | 1 | 11.5 |
| 7 | 11 | 0.43 | 0.47 | 0.91 | 1.5 | 11.1 | 10.64 | 2 | 6 | 1 | 13.6 |
| 8 | 12.9 | 0.47 | 0.51 | 0.91 | 1.7 | 13 | 12.54 | 2 | 6 | 1 | 15.7 |
| 9 | 14.7 | 0.58 | 0.62 | 0.91 | 1.7 | 14.8 | 14.34 | 2 | 6 | 1 | 18.2 |
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