Standard: GB 881 - 1976
Available sizes: 10 to 8 (7 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 881 |
| DIN | DIN EN 28737 |
| ISO | ISO 8737 |
| Size | P | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| 10 | 40.05 | 48 | L+65 | 40 | M30 | 5 | 2.5 | 25 | 8 |
| 12 | 60.05 | 64 | L+85 | 60 | M42 | 5 | 2.5 | 36 | 10 |
| 3 | 4.05 | 6 |
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.
| L+10 |
| 4 |
| M4 |
| 0.5 |
| 0.5 |
| 2.8 |
| 1.5 |
| 4 | 6.05 | 10 | L+15 | 6 | M6 | 1 | 0.5 | 4.5 | 2 |
| 5 | 10.05 | 12 | L+18 | 10 | M8 | 1.5 | 1 | 5.5 | 2 |
| 6 | 16.05 | 20 | L+30 | 16 | M12 | 1.5 | 1 | 9 | 4 |
| 8 | 25.05 | 32 | L+45 | 25 | M20 | 3 | 1.5 | 16 | 5 |
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