Standard: BS 916 - 1953
Available sizes: 1/2 to 9/16 (8 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| 1/2 | 8 | 1.71 | 0.935 | 10 | 1.480 | 1.450 | 0.875 |
| 1/4 | 18 | 0.61 | 0.270 | 22 | 0.525 | 0.515 | 0.250 |
| 3/4 | 5 | 2.78 | 1.580 | 8 | 2.410 | 2.365 | 1.500 |
| 3/8 |
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 |
| 1.06 |
| 0.530 |
| 16 |
| 0.920 |
| 0.900 |
| 0.500 |
| 5/16 | 14 | 0.82 | 0.395 | 18 | 0.710 | 0.695 | 0.375 |
| 5/8 | 6 | 2.56 | 1.455 | 8 | 2.220 | 2.175 | 1.375 |
| 7/16 | 10 | 1.39 | 0.728 | 12 | 1.200 | 1.175 | 0.687 |
| 9/16 | 7 | 2.15 | 1.205 | 9 | 1.860 | 1.815 | 1.125 |
© 2026 Ningbo Ruixi Metal Surface Technology Co., Ltd.. All rights reserved.