Standard: BS 1769 - 1951
Available sizes: 1 to 7/8 (6 sizes)
| Size | P | r | k_max | k_min | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| 1 | 5 | 4 | 3.18 | 1.352 | 2.75 | 1/8 | 3.75 | 2.69 | 1.272 |
| 1-1/8 | 4-1/2 | 4.5 | 3.61 | 1.482 | 3.125 | 1/8 | 4.25 | 3.065 | 1.394 |
| 1/2 | 11 | 1.75 | 1.23 | 0.522 | 1.0625 |
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.
| 1/16 |
| 1.5 |
| 1.0375 |
| 0.478 |
| 3/4 | 7 | 2.75 | 2.09 | 0.874 | 1.8125 | 1/8 | 2.5 | 1.7825 | 0.814 |
| 5/8 | 9 | 2.25 | 1.66 | 0.714 | 1.4375 | 1/16 | 2 | 1.4075 | 0.662 |
| 7/8 | 6 | 3.25 | 2.53 | 1.065 | 2.1875 | 1/8 | 3 | 2.1425 | 0.997 |
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