Standard: ANSI B 18.5
Available sizes: 1/4 to 7/16 (5 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| 1/4 | 0.3750 | 0.844 | 0.782 | 16 | 0.388 | 0.188 | 0.360 | 0.208 |
| 10# | 0.2500 | 0.594 | 0.563 | 20 | 0.260 | 0.125 | 0.237 | 0.145 |
| 3/8 | 0.7500 | 1.594 | 1.469 | 10 | 0.768 | 0.375 | 0.729 | 0.406 |
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 | 0.5000 | 1.094 | 1.032 | 13 | 0.515 | 0.250 | 0.483 | 0.270 |
| 7/16 | 1.0000 | 2.094 | 1.969 | 8 | 1.022 | 0.500 | 0.976 | 0.531 |
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