Standard: JIS B 1181 - 1993
Available sizes: M18 to M24 (4 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M18 | 2.5 | 16.9 | 18 | 0.2 | 21.6 | 1.5 | 2 | 27.7 | 32.95 | 0.8 | 20 |
| M20 | 3 | 20.2 | 21.5 | 0.2 | 25.9 | 2 | — | 33.25 | 39.55 | 0.8 | 24 |
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.
| M22 |
| 3.5 |
| 24.3 |
| 25.6 |
| 0.2 |
| 32.4 |
| 2 |
| — |
| 42.75 |
| 50.85 |
| 0.8 |
| 30 |
| M24 | 4 | 29.4 | 31 | 0.2 | 38.9 | 3 | — | 51.11 | 60.79 | 0.8 | 36 |
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