GB /T 13681.2 (GB) and ISO 21670 (ISO) are equivalent fastener standards that specify the same or very similar products. Both standards cover 2 fastener types in our database.
GB /T 13681.2 (GB standard) and ISO 21670 (ISO 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 13681.2 | ISO 21670 |
|---|---|---|
| Standard Body | GB | ISO |
| Product Types | 2 fastener types | |
| Interchangeable? | Yes — equivalent standard | |
| Product | Has Specs |
|---|---|
| Hexagon Weld Nuts with Flange | ✓ |
| Weld Hexagon Nuts with Flange | ✓ |
From: Hexagon Weld Nuts with Flange — applies to both GB /T 13681.2 and ISO 21670
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M10 | 2 | 8.1 | 25 | 4.25 | 3.75 | 1.5 | 3.7 | 36.5 | 35.5 | 3.5 | 18 |
| M5 | 1 | 5.1 | 10.6 | 2.25 | 1.75 |
Both GB /T 13681.2 and ISO 21670 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.
| / |
| 2.7 |
| 18.5 |
| 17.5 |
| 2.5 |
| 7 |
| M6 | 1.5 | 7.1 | 16.9 | 3.25 | 2.75 | 1.25 | 2.95 | 26.5 | 25.5 | 2.75 | 11.5 |
| M8 | 2 | 8.1 | 22.4 | 4.25 | 3.75 | 1.5 | 3.45 | 33.5 | 32.5 | 3.25 | 16 |
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