Standard: BS 4464 - 1969
Available sizes: (M3.5) to M8 (6 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| (M3.5) | 5.35 | 1.4 | 8.55 | 5.1 | 1.5 | 1.6 |
| M3 | 3.8 | 0.9 | 6.0 | 3.6 | 1 | 1.1 |
| M4 | 8.55 | 1.9 | 12.75 | 8.2 | 2 | 2.1 |
| M5 | 12.6 | 2.35 | 17.9 | 12.2 | 2.5 | 2.65 |
| M6 |
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.
| 16.9 |
| 3.3 |
| 24.3 |
| 16.3 |
| 3.5 |
| 3.7 |
| M8 | 19 | 3.3 | 26.4 | 18.3 | 3.5 | 3.7 |
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