Standard: CNS 4251 - 1980
Available sizes: (M1.8) to M3 (5 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (M1.8) | 0.4 | 0.3 | 6 | 0.5 | 0.9 | 16 | 3.8 | 1.2 | 1.2 | 3 | 0.7 |
| (M3.5) | 1.5 | 1.3 | 25 | 2.5 | 4.1 | 40 | 16 | 5 |
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.
| 5 |
| 12.5 |
| 3.5 |
| M2 | 0.5 | 0.5 | 8 | 0.8 | 1.25 | 19 | 5.5 | 1.5 | 1.5 | 4 | 1 |
| M2.5 | 0.7 | 0.6 | 10 | 1 | 1.7 | 22 | 7 | 2 | 2 | 5 | 1.4 |
| M3 | 1 | 0.9 | 16 | 1.6 | 2.6 | 28 | 10 | 3 | 3 | 8 | 2.2 |
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