Standard: ASME B 18.27
Available sizes: 0.197 to 9/32 (7 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 0.197 | NA7-23 | 0.026 | 0.030 | 0.015 | 0.017 | 0.215 | 0.217 | 0.036 | 0.042 | 0.211 | 0.013 |
| 0.276 | NA7-39 | 0.041 | 0.041 | 0.025 | 0.027 | 0.354 | 0.356 | 0.047 |
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.
| 0.053 |
| 0.349 |
| 0.023 |
| 1/4 | NA7-35 | 0.041 | 0.041 | 0.025 | 0.027 | 0.320 | 0.322 | 0.047 | 0.053 | 0.315 | 0.023 |
| 15/64 | NA7-31 | 0.041 | 0.041 | 0.025 | 0.027 | 0.281 | 0.283 | 0.047 | 0.053 | 0.276 | 0.023 |
| 3/16 | NA7-19 | 0.026 | 0.030 | 0.015 | 0.017 | 0.179 | 0.181 | 0.036 | 0.042 | 0.175 | 0.013 |
| 7/32 | NA7-27 | 0.041 | 0.041 | 0.025 | 0.027 | 0.250 | 0.252 | 0.047 | 0.053 | 0.245 | 0.023 |
| 9/32 | NA7-43 | 0.041 | 0.041 | 0.025 | 0.027 | 0.395 | 0.397 | 0.047 | 0.053 | 0.390 | 0.023 |
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