Standard: CNS 3121 - 1998
Available sizes: (M3.5) to M6 (8 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (M3.5) | 1.5 | 14.63 | / | 0.15 | 0.6 | 26 | / | 10 | 9.78 | / | 11.2 |
| M1.6 | 0.4 | 3.07 | / | 0.1 | 0.25 | 10 | / |
| 2 |
| 1.86 |
| / |
| 2.6 |
| M2 | 0.5 | 4.57 | / | 0.15 | 0.4 | 12 | / | 3 | 2.86 | / | 3.6 |
| M2.5 | 0.7 | 5.88 | / | 0.15 | 0.4 | 14 | / | 4 | 3.82 | / | 4.7 |
| M3 | 1 | 8.88 | / | 0.15 | 0.5 | 18 | / | 6 | 5.82 | / | 6.8 |
| M4 | 2 | 19.37 | / | 0.15 | 0.6 | 34 | 40 | 14 | 13.73 | / | 15.7 |
| M5 | 2.5 | 25.34 | 17.57 | 0.2 | 0.8 | 42 | 48 | 18 | 17.73 | / | 20.2 |
| M6 | 2.5 | 28.19 | 19.48 | 0.2 | 0.8 | 46 | 52 | 20 | 19.67 | / | 22.4 |
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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