Standard: ASME B 18.27
Available sizes: 0.394 to 5/8 (7 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 0.394 | NA4-42 | 0.105 | 0.04 | 0.035 | 0.037 | 0.394 | 0.397 | 0.042 | 0.052 | 0.388 | 0.033 |
| 0.428 | NA4-50 | 0.124 | 0.048 | 0.05 | 0.052 | 0.46 |
| 0.465 |
| 0.05 |
| 0.06 |
| 0.45 |
| 0.048 |
| 0.473 | NA4-62 | 0.134 | 0.048 | 0.05 | 0.052 | 0.575 | 0.58 | 0.05 | 0.06 | 0.565 | 0.048 |
| 0.591 | NA4-87 | 0.185 | 0.076 | 0.078 | 0.081 | 0.804 | 0.809 | 0.078 | 0.093 | 0.794 | 0.075 |
| 0.669 | NA4-112 | 0.225 | 0.091 | 0.093 | 0.096 | 1.036 | 1.046 | 0.093 | 0.108 | 1.021 | 0.09 |
| 1/2 | NA4-75 | 0.185 | 0.076 | 0.078 | 0.081 | 0.689 | 0.694 | 0.078 | 0.093 | 0.679 | 0.075 |
| 5/8 | NA4-98 | 0.185 | 0.076 | 0.078 | 0.081 | 0.906 | 0.911 | 0.078 | 0.093 | 0.896 | 0.075 |
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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