ISO 4161FlangeExternal hexagon
ISO 4161 M20 Flange
ISO 4161 M20 is a flange nut, on a M20 × 1.5 mm metric thread. A hex nut with a wide circular flange that spreads the clamping load and behaves like an integrated washer. Speeds up assembly versus nut + washer.
Diameter20 mm
Pitch1.5 mm
Socket size s30 mm
Height m20 mm
Flange Ø dc42.8 mm
HeadFlange
DriveExternal hexagon
Dimensions
- Standard
- ISO 4161
- Type
- Flange nut
- Size
- M20
- Thread
- M20 × 1.5
- Socket size s
- 30 mm
- Height m
- 20 mm
- Flange diameter dc
- 42.8 mm
- Drive
- External hexagon
- Head
- Flange
Nominal values in millimetres as published in ISO 4161. Estimated weight 42.451 g per piece in steel (42.722 g in stainless), calculated from the nominal geometry — real parts vary with tolerance and head chamfers.
Thread data
Full M20 thread pageDesignationM20 × 1.5 fine
Pitch1.5 mm
Major Ø20 mm
Pitch Ø19.03 mm
Minor Ø ext18.16 mm
Tap drillØ 18.5 mm