Standard: BS 1768 - 1963
Available sizes: 1/4 to 7/16 (4 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| 1/4 | 0.5 | 0.483 | 0.473 | 0.493 | 0.271 | 0.261 | 0.577 |
| 3/8 | 0.875 | 0.855 | 0.845 | 0.867 | 0.489 | 0.479 | 1.010 |
| 5/16 | 0.6875 | 0.668 | 0.658 | 0.6795 | 0.38 | 0.37 | 0.794 |
| 7/16 | 1.125 | 1.100 |
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.
| 1.090 |
| 1.115 |
| 0.651 |
| 0.631 |
| 1.300 |
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