Standard: ANSI B 18.21
Available sizes: 0# to 8# (8 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 0# | 0.084 | 0.084 | 0.084 | 0.156 | 0.151 | 0.084 | 0.079 | 0.028 | 0.022 | 0.156 | 0.025 |
| 1# | 0.109 | 0.109 | 0.109 | 0.219 | 0.214 | 0.109 | 0.104 | 0.028 | 0.022 | 0.219 | 0.025 |
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.
| 2# | 0.141 | 0.149 | 0.141 | 0.281 | 0.276 | 0.141 | 0.136 | 0.036 | 0.028 | 0.281 | 0.032 |
| 3# | 0.188 | 0.196 | 0.188 | 0.383 | 0.37 | 0.196 | 0.183 | 0.045 | 0.036 | 0.375 | 0.04 |
| 4# | 0.234 | 0.242 | 0.234 | 0.446 | 0.433 | 0.242 | 0.229 | 0.045 | 0.036 | 0.438 | 0.04 |
| 5# | 0.344 | 0.359 | 0.344 | 0.64 | 0.62 | 0.359 | 0.339 | 0.071 | 0.056 | 0.625 | 0.063 |
| 6# | 0.469 | 0.484 | 0.469 | 0.89 | 0.868 | 0.484 | 0.464 | 0.071 | 0.056 | 0.875 | 0.063 |
| 8# | 0.594 | 0.609 | 0.594 | 1.14 | 1.118 | 0.609 | 0.589 | 0.071 | 0.056 | 1.125 | 0.063 |
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