Standard: GB /T 879.2 - 2018
Available sizes: 2 to 4.5 (6 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 879.2 |
| DIN | DIN EN ISO 13337 |
| ISO | ISO 13337 |
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| 2 | 2.9 | 0.25 | 0.25 | 2.8 | 2.3 | 0.45 | 2.4 |
| 2.5 | 4 | 0.3 | 0.35 | 3.8 | 3.1 | 0.5 | 4.6 |
| 3 | 5.1 | 0.5 | 0.5 | 4.9 | 3.9 | 0.7 | 8.8 |
| 3.5 |
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.
| 6.7 |
| 0.7 |
| 0.75 |
| 6.4 |
| 4.9 |
| 0.9 |
| 18 |
| 4 | 10.8 | 2 | 1 | 10.5 | 8.5 | 2.4 | 40 |
| 4.5 | 13.8 | 2 | 1.2 | 13.5 | 11 | 2.4 | 66 |
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