Standard: BS 4183
Available sizes: (M3.5) to M4 (5 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| (M3.5) | 10 | 1.51 | 1.26 | 9.64 | 3 | 1.2 | 2.86 | 1.8 |
| (M4.5) | 20 | 2.81 | 2.56 | 19.48 | 6 | 2.4 | 5.82 | 3.6 |
| M2.5 | 6 | 1 | 0.86 | 5.7 |
| 1.8 |
| 0.72 |
| 1.66 |
| 1.08 |
| M3 | 8 | 1.2 | 1.06 | 7.64 | 2.4 | 0.96 | 2.26 | 1.44 |
| M4 | 16 | 2.31 | 2.06 | 15.57 | 4.8 | 1.92 | 4.62 | 2.88 |
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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