Standard: BS 1768 - 1963
Available sizes: (9/16) to 7/16 (7 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| (9/16) | 1.8750 | 1.797 | 1.275 | 1.8300 | 2.165 | 1.813 | 1.225 |
| 1/2 | 1.5000 | 1.463 | 1.015 | 1.4880 | 1.732 | 1.473 | 0.985 |
| 1/4 | 0.5000 | 0.473 | 0.333 | 0.4930 | 0.577 | 0.483 | 0.323 |
| 3/8 | 0.8750 | 0.845 |
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.
| 0.614 |
| 0.8670 |
| 1.010 |
| 0.855 |
| 0.604 |
| 5/16 | 0.6875 | 0.658 | 0.458 | 0.6795 | 0.794 | 0.668 | 0.448 |
| 5/8 | 2.2500 | 2.172 | 1.530 | 2.2050 | 2.598 | 2.188 | 1.470 |
| 7/16 | 1.1250 | 1.090 | 0.822 | 1.1150 | 1.300 | 1.100 | 0.802 |
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