Tool Sizes for Fastening Hardware
Metric Socket-Head Cap Screws
| Metric Clamp Screw |
Hex Wrench Size (mm) |
| M1.6 | 1.5 |
| M2 | 1.5 |
| M2.5 | 2.0 |
| M3 | 2.5 |
| M4 | 3.0 |
| M5 | 4.0 |
| M6 | 5.0 |
| M8 | 6.0 |
| M10 | 8.0 |
| M12 | 10.0 |
Metric Set Screws
| Metric Set Screw |
Hex Wrench Size (mm) |
| M2 | 0.9 |
| M2.5 | 1.3 |
| M3 | 1.5 |
| M4 | 2.0 |
| M5 | 2.5 |
| M6 | 3.0 |
| M8 | 4.0 |
| M10 | 5.0 |
Inch Socket-Head Cap Screws
| Inch Clamp Screw |
Hex Wrench Size (inches) |
| #4-40 | 3/32 |
| #6-32 | 7/64 |
| #8-32 | 9/64 |
| #10-32 | 5/32 |
| 1/4-28 | 3/16 |
| 5/16-24 | 1/4 |
| 3/8-24 | 5/16 |
| 1/2-20 | 3/8 |
Inch Set Screws
| Inch Set Screw |
Hex Wrench Size (inches) |
| #6-32 | 1/16 |
| #8-32 | 5/64 |
| #10-32 | 3/32 |
| 1/4-20 | 1/8 |
| 5/16-18 | 5/32 |
| 3/8-16 | 3/16 |
| 1/2-13 | 1/4 |