Standard: BS 2470 - 1973
Available sizes: 1/4 to 7/16 (5 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1/4 | 16 | 1.250 | 0.182 | 0.562 | 0.550 | 20 | 0.3750 | 0.368 | 5/16 | 0.3678 | 0.375 |
| 3/16 | 20 | 1.000 | 0.120 | 0.375 | 0.365 | 26 | 0.2500 |
| 0.244 |
| 3/16 |
| 0.2435 |
| 0.250 |
| 3/8 | 10 | 2.000 | 0.370 | 1.000 | 0.982 | 12 | 0.7500 | 0.740 | 9/16 | 0.7406 | 0.750 |
| 5/16 | 12 | 1.500 | 0.245 | 0.750 | 0.735 | 16 | 0.5000 | 0.492 | 3/8 | 0.4919 | 0.500 |
| 7/16 | 8 | 2.500 | 0.495 | 1.312 | 1.291 | 10 | 1.0000 | 0.988 | 5/8 | 0.9886 | 1.000 |
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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