Standard: UNI 7687
Available sizes: (M3.5) 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 | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|
| (M3.5) | 1.25 | 3.71 | 8.46 | 6.15 | 0.8 | 15.73 | 16 | 3.7 | 4 | 5.85 | 16 |
| M2 | 0.45 | 1.53 | 2.9 | 2.12 | 0.25 | 4.82 | 5 | 1.3 | 1 | 1.88 | 5 |
| M2.5 | 0.6 | 1.47 | 3.91 | 2.82 | 0.35 | 6.78 | 7 | 1.9 | 2 | 2.58 | 7 |
| M3 | 0.8 | 2.28 | 4.7 | 3.95 | 0.5 | 9.78 | 10 | 2.5 | 2 | 3.65 | 10 |
| M4 | 1.5 | 5.23 | 10 | 7.68 | 1 | 19.67 | 20 | 4.8 | 4 | 7.32 | 20 |
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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