Standard: ANSI B 18.21
Available sizes: 1/4×1 to 5/32×7/8 (8 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| 1/4×1 | 0.348 | 1.242 | 1.279 | 0.338 | 0.358 | 0.047 | 0.08 | 1.25 | 0.065 |
| 1/8×3/4 | 0.19 | 0.742 | 0.779 | 0.213 | 0.233 | 0.047 | 0.08 | 0.75 | 0.065 |
| 1/8×5/8 | 0.16 | 0.742 | 0.779 | 0.15 |
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.
| 0.17 |
| 0.047 |
| 0.08 |
| 0.75 |
| 0.065 |
| 3/16×1 | 0.285 | 1.492 | 1.529 | 0.275 | 0.295 | 0.047 | 0.08 | 1.5 | 0.065 |
| 3/16×1-1/2 | 0.348 | 0.992 | 1.029 | 0.338 | 0.358 | 0.047 | 0.08 | 1 | 0.065 |
| 3/16×1-1/4 | 0.285 | 1.992 | 2.029 | 0.275 | 0.295 | 0.047 | 0.08 | 2 | 0.065 |
| 3/16×3/4 | 0.285 | 0.992 | 1.029 | 0.275 | 0.295 | 0.047 | 0.08 | 1 | 0.065 |
| 5/32×7/8 | 0.19 | 1.242 | 1.279 | 0.213 | 0.233 | 0.047 | 0.08 | 1.25 | 0.065 |
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