Standard: DIN 7504
Available sizes: (ST3.9) to ST4.2 (3 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (ST3.9) | 1.6 | 0.7 | 1.51 | 8.71 | 4.45 | 0.9 | 10.5 | 1.2 | 1.26 | 9.8 | 4.15 |
| ST3.5 | 1.3 | 0.5 | 1.2 | 5.96 | 3.45 | 0.6 | 8.3 |
| 1 |
| 1.06 |
| 7.6 |
| 3.2 |
| ST4.2 | 1.8 | 0.9 | 1.91 | 10.95 | 6.45 | 1 | 13.5 | 1.6 | 1.66 | 12.2 | 6.15 |
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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