Standard: BS 1083 - 1965
Available sizes: 1/4 to 7/16 (4 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| 1/4 | 18 | 0.250 | 0.240 | 22 | 0.525 | 0.498 | 0.61 | 0.518 | 0.508 |
| 3/8 | 12 | 0.500 | 0.490 | 16 | 0.920 | 0.890 | 1.06 | 0.912 | 0.900 |
| 5/16 | 14 |
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.
| 0.375 |
| 0.365 |
| 18 |
| 0.710 |
| 0.680 |
| 0.82 |
| 0.702 |
| 0.690 |
| 7/16 | 10 | 0.687 | 0.677 | 12 | 1.200 | 1.165 | 1.39 | 1.190 | 1.175 |
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