Standard: BS 1981 - 1991
Available sizes: (3#) to 5# (4 sizes)
| Size | P | s_max | s_min | k_nominal |
|---|---|---|---|---|
| (3#) | 0.187 | 0.181 | 0.07 | 0.058 |
| 2# | 0.187 | 0.181 | 0.055 | 0.044 |
| 4# | 0.25 | 0.244 | 0.11 | 0.096 |
| 5# | 0.312 | 0.305 | 0.155 | 0.139 |
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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