Standard: BS 4464 - 1969
Available sizes: (M2.2) to M5 (8 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| (M2.2) | 3.8 | 1.2 | 0.8 | 3.6 | 1.3 | 0.7 | 6.6 | 1.4 | 0.9 |
| (M3.5) | 12.6 | 3.8 | 2.5 | 12.2 | 4 | 2.35 | 21 | 4.2 | 2.65 |
| M1.6 | 2.3 | 0.8 | 0.5 | 2.1 | 0.9 |
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.
| 0.4 |
| 4.3 |
| 1 |
| 0.6 |
| M2 | 2.8 | 0.9 | 0.6 | 2.6 | 1 | 0.5 | 5 | 1.1 | 0.7 |
| M2.5 | 5.35 | 1.7 | 1.2 | 5.1 | 1.8 | 1.1 | 9.15 | 1.9 | 1.3 |
| M3 | 8.55 | 2.85 | 2 | 8.2 | 3 | 1.9 | 14.85 | 3.15 | 2.1 |
| M4 | 16.9 | 4.8 | 3.5 | 16.3 | 5 | 3.3 | 27.3 | 5.2 | 3.7 |
| M5 | 21.1 | 5.8 | 4 | 20.3 | 6 | 3.8 | 33.5 | 6.2 | 4.2 |
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