Standard: ANSI B 18.6
Available sizes: M3 to M8 (5 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 62.1, GB /T 62.3 |
| NF | NF E 27-454 |
| DIN | DIN 315 |
| JIS | JIS B 1185 Type 1, JIS B 1185 Type 3 |
| UNI | UNI 5448(B) |
| Size | P | e | r | k_max | k_min | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| M3 | 0.7 | 2.5 | 4 | 24 | 10 | 8 | 1.5 | 2 | 7 | 4 |
| M4 | 1 | 3.5 | 5 | 32 | 14 | 12 | 2.5 | 3 | 10 | 6 |
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.
| M5 |
| 1.5 |
| 5 |
| 7 |
| 48 |
| 22 |
| 18 |
| 3.5 |
| 4 |
| 15 |
| 10 |
| M6 | 2 | 7 | 9 | 64 | 30 | 26 | 5 | 6 | 23 | 14 |
| M8 | 2 | 8 | 10 | 72 | 32 | 30 | 6 | 7 | 26 | 14 |
© 2026 Ningbo Ruixi Metal Surface Technology Co., Ltd.. All rights reserved.