Standard: BS 325 - 1947
Available sizes: 1/2 to 7/16 (5 sizes)
| Size | P | s_max | s_min | k_nominal |
|---|---|---|---|---|
| 1/2 | 8 | 1.839 | 0.625 | 0.25 |
| 1/4 | 18 | 0.574 | 0.234 | 0.078 |
| 3/8 | 11 | 1.149 | 0.42 | 0.156 |
| 5/16 | 14 | 0.805 | 0.327 | 0.109 |
| 7/16 | 9 | 1.609 | 0.561 | 0.219 |
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.
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