DIN 931Hexagon headExternal hexagon
DIN 931 M6 × 20 Hexagon head
DIN 931 M6 × 20 is a hexagon head bolt with a 20 mm nominal length, on a M6 × 1 mm metric thread. Same head as DIN 933 but with an unthreaded shank under the head. The plain shank carries shear load, which is why these are preferred for structural steelwork and machinery frames.
Diameter6 mm
Length20 mm
Pitch1 mm
Socket size s10 mm
Head height k4 mm
HeadHexagon head
DriveExternal hexagon
Dimensions
- Standard
- DIN 931
- Type
- Hexagon head bolt
- Size
- M6 × 20
- Thread
- M6 × 1
- Length L
- 20 mm
- Socket size s
- 10 mm
- Head height k
- 4 mm
- Drive
- External hexagon
- Head
- Hexagon head
Nominal values in millimetres as published in DIN 931. Estimated weight 4.439 g per piece in steel (4.467 g in stainless), calculated from the nominal geometry — real parts vary with tolerance and head chamfers.
Thread data
Full M6 thread pageDesignationM6 × 1
Pitch1 mm
Major Ø6 mm
Pitch Ø5.35 mm
Minor Ø ext4.77 mm
Tap drillØ 5 mm
Other lengthsDIN 931 M6
All M6 specificationsInterchangeability
DIN 931 is catalogued with ISO 4014 as its equivalent designation. Dimensions are compared field by field rather than assumed identical.