Standard: ANSI B 18.21
Available sizes: 0# to 8# (8 sizes)
| Size | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| 0# | 0.25 | 0.245 | 0.094 | 0.089 | 0.025 | 0.016 | 0.25 | 0.02 |
| 10# | 0.905 | 0.868 | 0.39 | 0.37 | 0.104 | 0.064 | 0.875 | 0.083 |
| 12# | 0.937 | 0.915 | 0.484 | 0.464 | 0.08 | 0.051 | 0.922 | 0.065 |
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# | 0.39 | 0.37 | 0.164 | 0.151 | 0.065 | 0.036 | 0.375 | 0.049 |
| 3/16 | 1.03 | 0.993 | 0.453 | 0.433 | 0.104 | 0.064 | 1 | 0.083 |
| 4# | 0.515 | 0.495 | 0.227 | 0.214 | 0.065 | 0.036 | 0.5 | 0.049 |
| 6# | 0.577 | 0.557 | 0.265 | 0.245 | 0.08 | 0.051 | 0.562 | 0.065 |
| 8# | 0.749 | 0.727 | 0.327 | 0.307 | 0.08 | 0.051 | 0.734 | 0.065 |
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