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M20 nut size
30 mm wrench
wrench size for M20 hex nut
M20 hex nut — standard metric hexagonal nut.
Full specification
| System | Metric |
| Nominal diameter | 20 mm |
| Wrench size (across flats) | 30 mm |
| Nut thickness | 16 mm |
| Common grade / class | Class 8 |
About M20 nuts
M20 hex nuts are standard metric hexagonal nuts used with M20 bolts and threaded rods.
The wrench size 30 mm is measured across the flats of the hexagon. The nut thickness is 16 mm.
Class 8 indicates the strength rating. These nuts are suitable for general-purpose applications.
Frequently asked questions
- What size wrench fits M20 nut?
- M20 nut uses a 30 mm wrench.
- How thick is a M20 nut?
- A standard M20 hex nut is 16 mm thick.
- What is the difference between M20 nut classes?
- Class Class 8 indicates the strength rating. Higher numbers mean stronger nuts.