Standard: BS 1210 - 1963
Available sizes: 3# to 8# (6 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| 3# | 0.108 | 0.216 | 0.205 | 0.113 | 0.104 | 0.123 | 1 | 22 | 0.064 |
| 4# | 0.136 | 0.272 | 0.258 | 0.141 | 0.131 | 0.170 | 2 | 18 | 0.082 |
| 5# |
| 0.164 |
| 0.328 |
| 0.312 |
| 0.169 |
| 0.159 |
| 0.197 |
| 2 |
| 14 |
| 0.100 |
| 6# | 0.192 | 0.384 | 0.365 | 0.197 | 0.186 | 0.208 | 2 | 12 | 0.117 |
| 7# | 0.248 | 0.496 | 0.472 | 0.253 | 0.238 | 0.299 | 3 | 9 | 0.153 |
| 8# | 0.276 | 0.552 | 0.524 | 0.281 | 0.266 | 0.315 | 3 | 8 | 0.170 |
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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