Standard: CNS 4374 - 1987
Available sizes: (M3.5) to M6 (5 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| (M3.5) | 10 | 11 | 4.5 | 6.5 | 22 | 3 | 3.7 |
| M3 | 8 | 9.5 | 3.2 | 5 | 19 | 2.5 | 2.7 |
| M4 | 13 | 15 | 6 | 9 | 31.5 | 4 | 8.4 |
| M5 | 17 | 17.5 | 7 |
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.
| 12 |
| 37 |
| 5 |
| 13.6 |
| M6 | 20.5 | 24 | 9.5 | 16 | 53 | 5.5 | 32.5 |
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