Standard: BS 2470 - 1973
Available sizes: 1/4 to 7/16 (5 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| 1/4 | 16 | 0.250 | 0.241 | 20 | 3/16 | 0.089 | 0.150 | 0.099 |
| 3/16 | 20 | 0.156 | 0.149 | 26 | 1/8 | 0.059 | 0.100 | 0.067 |
| 3/8 | 10 | 0.562 | 0.549 | 12 |
| 3/8 |
| 0.180 |
| 0.300 |
| 0.196 |
| 5/16 | 12 | 0.344 | 0.334 | 16 | 1/4 | 0.120 | 0.200 | 0.130 |
| 7/16 | 8 | 0.750 | 0.734 | 10 | 9/16 | 0.240 | 0.450 | 0.260 |
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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