Standard: JIS B 1181 - 1993
Available sizes: (M2.2) to M5 (8 sizes)
| Size | P | r | k_max | k_min | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| (M2.2) | 0.5 | 5.3 | 1.8 | 1.55 | 2.4 | 5.3 | 6.4 | 2.15 | 5.5 |
| (M3.5) | 1 | 10.8 | 4.2 | 3.9 | 5.5 | 10.75 | 12.7 | 5.2 | 11 |
| (M4.5) | 2 | 21 | 8 | 7.64 | 11 |
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.
| 21.65 |
| 25.4 |
| 10.57 |
| 22 |
| M2 | 0.45 | 4.3 | 1.4 | 1.15 | 1.8 | 4.3 | 5.2 | 1.55 | 4.5 |
| M2.5 | 0.7 | 6.8 | 2.4 | 2.15 | 3.2 | 6.8 | 8.1 | 2.9 | 7 |
| M3 | 0.8 | 7.8 | 3.2 | 2.9 | 4 | 7.8 | 9.2 | 3.7 | 8 |
| M4 | 1.5 | 16.5 | 6 | 5.7 | 8 | 16.75 | 19.6 | 7.64 | 17 |
| M5 | 2 | 23 | 10 | 9.64 | 13 | 23.65 | 27.7 | 12.57 | 24 |
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