Standard: GB /T 3748 - 2008
Available sizes: (M20) to M22 (6 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (M20) | L | 65.3 | 65 | 24 | 43 | 10 | 28 | 42.8 | 38 | 2 | 43.2 |
| M12 | L | 49.3 | 49 | 6 | 34 | 25 | 8 | 33.8 |
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.
| 30 |
| 1.5 |
| 34.2 |
| M14 | L | 53.3 | 53 | 10 | 36 | 25 | 12 | 35.8 | 32 | 1.5 | 36.2 |
| M16 | L | 56.3 | 56 | 12 | 38 | 25 | 15 | 37.8 | 34 | 1.5 | 38.2 |
| M18 | L | 59.3 | 59 | 15 | 40 | 16 | 18 | 39.8 | 36 | 1.5 | 40.2 |
| M22 | L | 72.3 | 72 | 30 | 47 | 10 | 35 | 46.8 | 42 | 2 | 47.2 |
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