Standard: ISO 14581 - 2022
Available sizes: (M2.5) to M4 (5 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 2673.1 |
| ISO | ISO 14581 |
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (M2.5) | 0.6 | 0.15 | 0.9 | 7.3 | 6.94 | 1.2 |
| 38 |
| 2.35 |
| 1.995 |
| 8.2 |
| 3.05 |
| (M3.5) | 1.25 | 0.4 | 2 | 15.8 | 15.37 | 3.13 | 38 | 4.65 | 4.06 | 17.3 | 7.1 |
| M2 | 0.45 | 0.1 | 0.6 | 4.7 | 4.4 | 0.9 | 25 | 1.5 | 1.224 | 5.5 | 2.15 |
| M3 | 0.8 | 0.2 | 1.3 | 9.3 | 8.94 | 2 | 38 | 2.7 | 2.28 | 10.4 | 4.4 |
| M4 | 1.5 | 0.4 | 2.5 | 18.3 | 17.78 | 3.75 | 38 | 5 | 4.4 | 20 | 8.9 |
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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