Standard: GB /T 2671.1 - 2004
Available sizes: (M3.5) to M4 (5 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 2671.1 |
| DIN | DIN EN ISO 14580 |
| ISO | ISO 14580 |
| Size | P | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| (M3.5) | 1.25 | 5.50 | T45 | 13.00 | 12.73 | 3.05 |
| 2.66 |
| 5.80 |
| 7.95 |
| M2 | 0.45 | 1.71 | T8 | 4.50 | 4.32 | 0.91 | 0.78 | 1.85 | 2.4 |
| M2.5 | 0.6 | 2.46 | T15 | 6.00 | 5.82 | 1.33 | 1.07 | 2.60 | 3.35 |
| M3 | 0.8 | 3.47 | T25 | 8.50 | 8.28 | 1.91 | 1.52 | 3.65 | 4.5 |
| M4 | 1.5 | 6.54 | T50 | 16.00 | 15.73 | 3.43 | 3.04 | 6.90 | 8.95 |
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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