Standard: GB 818 - 1985
Available sizes: M1.6 to M4 (5 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 818 |
| NF | NF E 25-121 |
| DIN | DIN EN ISO 7045 |
| ISO | ISO 7045 |
| UNI | UNI 7687 |
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| M1.6 | 0.4 | 1.46 | 0 | 4 | 3.7 | 1.6 |
| M2 | 0.5 | 2.26 | 1 | 5.6 | 5.3 | 2.4 |
| M2.5 | 0.8 | 3.52 | 2 | 9.5 | 9.14 | 3.7 |
| M3 | 1.25 | 5.7 | 4 | 16 |
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.
| 15.57 |
| 6 |
| M4 | 1.5 | 7.14 | 4 | 20 | 19.48 | 7.5 |
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