This page covers M5 Hex Flange Nuts to ISO 4161 / DIN 6923: the full dimensional row, hole and tool sizes, proof-load data and typical applications. All values are taken from the governing standards (ISO 4161 / DIN 6923 together with ISO 273, ISO 724 and ISO 898-1 where applicable).
M5 Dimensional Row (ISO 4161 / DIN 6923)
| Size | Pitch (mm) | Flange diameter dc (mm) | Nut height m (mm) | Width across flats s (mm) | Reference standard |
|---|---|---|---|---|---|
| M5 | 0.8 | 11.8 | 5.0 | 8.0 | ISO 4161 / DIN 6923 |
Spanner & Drive for M5 Hex Flange Nuts
M5 Hex Flange Nuts have a width across flats of 8.0 mm — fit a 8.0 mm open-ended spanner or socket. Use a 6-point socket for tight clearances and to reduce rounding; for repeated assembly choose a torque wrench so the joint preload is repeatable.
Common Applications for M5 Hex Flange Nuts
M5 Hex Flange Nuts are commonly specified for paired with the same-size screws on PCB hardware, light enclosures and small-scale assemblies.
Installation Tips for M5 Hex Flange Nuts
- Use a 6-point socket where access allows — 12-point sockets are more prone to rounding the corners on smaller sizes.
- On flanged or serrated variants, do NOT add a separate flat washer — the flange already spreads the load and the washer can defeat the locking serrations.
- At M5 the joint is sensitive to over-torque — use a torque-limiting driver and check the head doesn't bury into a softer counterpart.
Mating Parts for M5
Pair M5 with the matching M5 bolt or screw, plus a M5 flat washer where required to distribute load on softer materials.