Standard: DIN 7504
Available sizes: (ST3.9) to ST4.2 (4 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 15856.3 |
| DIN | DIN EN ISO 15483 |
| ISO | ISO 15483 |
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (ST3.9) | 1.8 | 7 | 3 |
| 1.7 |
| 4.8 |
| 1.8 |
| 10.8 |
| 2.1 |
| 9.4 |
| 10.37 |
| 3.4 |
| ST2.9 | 1.3 | 4.6 | 2 | 1.2 | 2.8 | 1.3 | 6.8 | 1.4 | 5.4 | 6.44 | 2.1 |
| ST3.5 | 1.4 | 4.9 | 2 | 1.4 | 3.6 | 1.4 | 8.1 | 1.6 | 6.6 | 7.74 | 2.5 |
| ST4.2 | 1.8 | 7.4 | 3 | 2 | 5.8 | 1.8 | 12.4 | 2.4 | 11.1 | 11.97 | 3.8 |
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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