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 | 2.2 | 1.8 | 5.2 | 0.7 | 1.1 | 6.3 | 1 | 3.4 | 5.5 | 1.7 |
| ST2.9 | 1.4 | 3.2 | 2.7 | 8 | 1 | 1.4 | 9.4 |
| 2 |
| 5.2 |
| 8.4 |
| 2.6 |
| ST3.5 | 1.8 | 3.45 | 2.95 | 9.9 | 1.3 | 1.8 | 11.5 | 3 | 6.7 | 10.3 | 3 |
| ST4.2 | 2.1 | 5.25 | 4.75 | 15.4 | 2 | 2.1 | 17.3 | 4 | 9.6 | 15.8 | 4.65 |
| ST4.8 | 2.1 | 6 | 5.5 | 17.8 | 2.3 | 2.1 | 20 | 4 | 10.4 | 18.3 | 5.25 |
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.
© 2026 Ningbo Ruixi Metal Surface Technology Co., Ltd.. All rights reserved.