Standard: NF E 25
Available sizes: 3 to 4 (2 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 3 | 4.1 | 7 | 1.8 | 13.65 | 1 | 4.4 | 14 | 0.96 | 1.4 | 14.35 | 1.04 |
| 4 | 6.1 | 10 | 2.5 | 17.65 | 1.4 | 6.4 | 18 | 1.36 |
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.
| 2.1 |
| 18.35 |
| 1.44 |
© 2026 Ningbo Ruixi Metal Surface Technology Co., Ltd.. All rights reserved.