Standard: GB /T 68 - 2000
Available sizes: (M3.5) to M3 (5 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 68 |
| NF | NF E 25-123 |
| DIN | DIN EN ISO 2009 |
| ISO | ISO 2009 |
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (M3.5) |
| 1.5 |
| 2.6 |
| 2.56 |
| 18.3 |
| 17.78 |
| 3 |
| 38 |
| 2.5 |
| 2.81 |
| 20 |
| 5 |
| M1.6 | 0.4 | 0.6 | 0.56 | 3.8 | 3.5 | 0.8 | 25 | 0.5 | 0.7 | 4.4 | 1.2 |
| M2 | 0.5 | 0.85 | 0.86 | 5.5 | 5.2 | 1 | 25 | 0.8 | 1 | 6.3 | 1.65 |
| M2.5 | 0.7 | 1.3 | 1.26 | 8.4 | 8.04 | 1.4 | 38 | 1.2 | 1.51 | 9.4 | 2.7 |
| M3 | 1 | 1.6 | 1.66 | 11.3 | 10.87 | 2 | 38 | 1.6 | 1.91 | 12.6 | 3.3 |
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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