GB /T 818 (GB) and NF E 25-121 (NF) are equivalent fastener standards that specify the same or very similar products. Both standards cover 7 fastener types in our database.
GB /T 818 (GB standard) and NF E 25-121 (NF standard) are equivalent standards that define the same fastener geometry and mechanical requirements. Minor differences may exist in tolerances, marking requirements, or referenced test methods, but the products are interchangeable in most applications. Always verify specific project requirements with your engineer.
| Property | GB /T 818 | NF E 25-121 |
|---|---|---|
| Standard Body | GB | NF |
| Product Types | 7 fastener types | |
| Interchangeable? | Yes — equivalent standard | |
From: Cross Recessed Pan Head Screws — applies to both GB /T 818 and NF E 25-121
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| M1.6 | 0.4 | 1.46 | 0 | 4 | 3.7 | 1.6 |
| M2 | 0.5 | 2.26 | 1 | 5.6 | 5.3 | 2.4 |
| M2.5 | 0.8 | 3.52 | 2 | 9.5 | 9.14 | 3.7 |
| M3 | 1.25 |
Both GB /T 818 and NF E 25-121 fasteners are available with various surface treatments. Common options for these standards include:
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.
| ✓ |
| Recessed Raised Cheese (Filister) Head Screws - ISO Metric Coarse Thread - Product Grade A | ✓ |
| 5.7 |
| 4 |
| 16 |
| 15.57 |
| 6 |
| M4 | 1.5 | 7.14 | 4 | 20 | 19.48 | 7.5 |
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