Standard: NF E 25
Available sizes: 2.5 to 5 (4 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2.5 | 3.4 | 8 | 1.1 | 8.21 | 0.5 | 3.1 | 8.5 | 0.47 | 1.5 | 8.79 | 0.53 |
| 3 | 4.4 | 8 | 1.4 | 10.65 | 0.6 | 4.1 | 11 |
| 0.57 |
| 1.9 |
| 11.35 |
| 0.63 |
| 4 | 6.46 | 8 | 1.75 | 13.65 | 0.7 | 6.1 | 14 | 0.67 | 2.3 | 14.35 | 0.73 |
| 5 | 7.56 | 10 | 1.85 | 15.65 | 0.8 | 7.2 | 16 | 0.77 | 2.5 | 16.35 | 0.83 |
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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