Standard: BS 1768 - 1963
Available sizes: 1/4 to 7/16 (4 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| 1/4 | 0.5000 | 0.094 | 0.261 | 0.177 | 0.4930 | 0.577 | 0.104 | 0.094 | 0.271 | 0.167 |
| 3/8 | 0.8750 | 0.156 | 0.479 | 0.333 | 0.8670 | 1.010 | 0.166 | 0.156 | 0.489 | 0.323 |
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.
| 5/16 | 0.6875 | 0.125 | 0.370 | 0.255 | 0.6795 | 0.794 | 0.135 | 0.125 | 0.380 | 0.245 |
| 7/16 | 1.1250 | 0.219 | 0.631 | 0.432 | 1.1150 | 1.300 | 0.198 | 0.188 | 0.651 | 0.412 |
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