Standard: Q 371
Available sizes: M4 to M8 (4 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M4 | 9.93 | 0.7 | 1 | 0.8 | 4.2 | 0.9 | 0.7 | 8 | 7.64 | 1 | 3.9 |
| M5 | 16.34 | 1.2 | 1.5 | 0.8 | 6.5 | 1.1 | 0.9 | 13 | 12.57 | 1 | 6.14 |
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.
| M6 |
| 22.84 |
| 1.6 |
| 2 |
| 1 |
| 9.5 |
| 1.5 |
| 1.3 |
| 18 |
| 17.57 |
| 1.2 |
| 9.14 |
| M8 | 30.11 | 2.1 | 2.5 | — | 13 | 1.7 | 1.5 | 24 | 23.16 | — | 12.3 |
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