Standard: JIS B 1122
Available sizes: ST2.2 to ST4.8 (5 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| ST2.2 | 1.1 | 3 | 1.8 | 2.4 | 2.15 | 1.1 | 5.6 | 3 | 1.4 | 5.3 | 1 |
| ST2.9 | 1.4 | 4.4 | 2.4 | 3.1 | 2.8 | 1.4 | 8 |
| 4.4 |
| 1.9 |
| 7.64 |
| 2 |
| ST3.5 | 1.8 | 6.2 | 3.1 | 4 | 3.7 | 1.8 | 11 | 6.4 | 2.6 | 10.57 | 3 |
| ST4.2 | 2.1 | 8.9 | 4.7 | 6 | 5.6 | 2.1 | 16 | 9 | 4.15 | 15.57 | 4 |
| ST4.8 | 2.1 | 10.1 | 5.8 | 7.5 | 7.1 | 2.1 | 20 | 10.1 | 5.2 | 19.48 | 4 |
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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