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M5 nut size
8 mm wrench
wrench size for M5 hex nut
M5 hex nut — standard metric hexagonal nut.
Full specification
| System | Metric |
| Nominal diameter | 5 mm |
| Wrench size (across flats) | 8 mm |
| Nut thickness | 4 mm |
| Common grade / class | Class 8 |
About M5 nuts
M5 hex nuts are standard metric hexagonal nuts used with M5 bolts and threaded rods.
The wrench size 8 mm is measured across the flats of the hexagon. The nut thickness is 4 mm.
Class 8 indicates the strength rating. These nuts are suitable for general-purpose applications.
Frequently asked questions
- What size wrench fits M5 nut?
- M5 nut uses a 8 mm wrench.
- How thick is a M5 nut?
- A standard M5 hex nut is 4 mm thick.
- What is the difference between M5 nut classes?
- Class Class 8 indicates the strength rating. Higher numbers mean stronger nuts.