Standard: NF E 25
Available sizes: (M3.5) to M6 (8 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 6170 |
| IS | IS 1364(-3) |
| DIN | DIN EN ISO 4032 |
| ISO | ISO 4032 |
| UNI | UNI 5588 |
| ANSI | ASME/ANSI B 18.2.4.1M |
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| (M3.5) | 1.5 | 16 | 15.73 | 17.77 | 8.4 | 8.04 |
| M1.6 | 0.4 | 4 | 3.82 | 4.32 | 1.6 | 1.35 |
| M2 | 0.5 | 5.5 | 5.32 | 6.01 | 2.4 | 2.15 |
| M2.5 | 0.7 | 7 | 6.78 | 7.66 |
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.
| 3.2 |
| 2.9 |
| M3 | 1 | 10 | 9.78 | 11.05 | 5.2 | 4.9 |
| M4 | 2 | 21 | 20.67 | 23.36 | 12.8 | 12.1 |
| M5 | 2.5 | 27 | 26.16 | 29.56 | 15.8 | 15.1 |
| M6 | 2.5 | 30 | 29.16 | 32.95 | 18 | 16.9 |
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