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M4 nut size
7 mm wrench
wrench size for M4 hex nut
M4 hex nut — standard metric hexagonal nut.
Full specification
| System | Metric |
| Nominal diameter | 4 mm |
| Wrench size (across flats) | 7 mm |
| Nut thickness | 3.2 mm |
| Common grade / class | Class 8 |
About M4 nuts
M4 hex nuts are standard metric hexagonal nuts used with M4 bolts and threaded rods.
The wrench size 7 mm is measured across the flats of the hexagon. The nut thickness is 3.2 mm.
Class 8 indicates the strength rating. These nuts are suitable for general-purpose applications.
Frequently asked questions
- What size wrench fits M4 nut?
- M4 nut uses a 7 mm wrench.
- How thick is a M4 nut?
- A standard M4 hex nut is 3.2 mm thick.
- What is the difference between M4 nut classes?
- Class Class 8 indicates the strength rating. Higher numbers mean stronger nuts.