Standard: GB 9074.21 - 1988
Available sizes: ST2.9 to ST4.2 (3 sizes)
| Size | P | s_max | s_min |
|---|---|---|---|
| ST2.9 | 1.3 | 1 | 11 |
| ST3.5 | 1.6 | 1.6 | 15 |
| ST4.2 | 2.1 | 2 | 21 |
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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