Handan Haosheng Fastener Co.,Ltd OEM Fasteners Manufacturers China
| Thread Size d | M5 | M6 | M8 | M10 | M10 | M12 | M12 | M16 | M20 | |
| P | Pitch（Coarse thread） | 0.8 | 1 | 1.25 | 1.5 | 1.5 | 1.75 | 1.75 | 2 | 2.5 |
| dw | min | 6.7 | 8.7 | 11.5 | 14.5 | 15.5 | 16.5 | 17.2 | 22 | 27.7 |
| e | ≈ | 11.3 | 14.1 | 18.4 | 22.6 | 24 | 25.4 | 26.9 | 33.9 | 42.4 |
| m | Nominal Size | 4 | 5 | 6.5 | 8 | 8 | 10 | 10 | 13 | 16 |
| max | 4.6 | 5.6 | 7.25 | 8.75 | 8.75 | 10.75 | 10.75 | 13.9 | 16.9 | |
| min | 3.4 | 4.4 | 5.75 | 7.25 | 7.25 | 9.25 | 9.25 | 12.1 | 15.1 | |
| m1 | min | 2.4 | 3.1 | 4 | 5.1 | 5.1 | 6.4 | 6.4 | 8.5 | 10.6 |
| s | max | 8 | 10 | 13 | 16 | 17 | 18 | 19 | 24 | 30 |
| min | 7.64 | 9.64 | 12.57 | 15.57 | 16.57 | 17.57 | 18.48 | 23.16 | 29.16 | |
| per 1000 units ≈ kg | 1.31 | 2.77 | 5.5 | 10.7 | 13 | 16.3 | 19.1 | 38.2 | 73.5 | |
What is DIN 557 Square Nuts
Metric DIN 557 regular pattern square nuts are four sided nuts. Their geometry provides a greater surface area to apply higher torque when tightening and also a greater surface are in contact with the part being fastened, thereby increasing the resistance to loosening.
