Standard: GB /T 70.3 - 2023
Available sizes: M2 to M6 (6 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 70.3 |
| DIN | DIN EN ISO 10642 |
| ISO | ISO 10642 |
| UNI | UNI 5933 |
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M2 | 0.45 |
| 0.1 |
| 1.408 |
| 4.8 |
| 2.5 |
| / |
| 5.88 |
| 1.733 |
| 1.69 |
| 5.08 |
| 2.36 |
| M2.5 | 0.7 | 0.2 | 2.121 | 7.53 | 4 | 20 | 8.96 | 2.873 | 2.48 | 7.96 | 3.82 |
| M3 | 1 | 0.25 | 3.218 | 11.34 | 6 | 24 | 13.44 | 4.583 | 3.72 | 12.16 | 5.82 |
| M4 | 1.5 | 0.4 | 5.563 | 19.22 | 10 | 32 | 22.4 | 6.863 | 6.2 | 20.69 | 9.78 |
| M5 | 2 | 0.6 | 7.588 | 26.52 | 14 | 42 | 30.8 | 11.429 | 8.4 | 28.31 | 13.73 |
| M6 | 2.5 | 0.8 | 9.037 | 35.4 | 20 | 60 | 40.32 | 13.716 | 10.16 | 36.75 | 19.67 |
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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