Standard: GB /T 75 - 2018
Available sizes: (M3.5) to M4 (6 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB 75 |
| DIN | DIN EN 27435 |
| ISO | ISO 7435 |
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| (M3.5) | 1.5 | 5.3 | 1.66 | 1.91 | 6.64 | 7 | 3 | 5 | 1.6 | 2.4 |
| M1.6 | 0.4 | 1.25 | 0.31 | 0.45 | 0.75 | 1 | 0.84 | 1 | 0.25 | 0.64 |
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.
| M2 | 0.5 | 1.75 | 0.46 | 0.6 | 1.75 | 2 | 1.05 | 1.5 | 0.4 | 0.8 |
| M2.5 | 0.7 | 2.25 | 0.66 | 0.8 | 2.25 | 2.5 | 1.42 | 2 | 0.6 | 1.12 |
| M3 | 1 | 3.25 | 1.06 | 1.2 | 3.7 | 4 | 2 | 3 | 1 | 1.6 |
| M4 | 1.75 | 6.3 | 2.06 | 2.31 | 8.14 | 8.5 | 3.6 | 6 | 2 | 2.8 |
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