DIN 7991Countersunk head (90°)Hexagon socket
DIN 7991 M4 × 8 Countersunk head (90°)
DIN 7991 M4 × 8 is a socket countersunk head screw with a 8 mm nominal length, on a M4 × 0.7 mm metric thread. Flat head version of the socket screw. The 90° cone seats flush in a matching countersink so nothing protrudes above the surface.
Diameter4 mm
Length8 mm
Pitch0.7 mm
Socket size s2.5 mm
Head Ø dk8 mm
HeadCountersunk head (90°)
DriveHexagon socket
Dimensions
- Standard
- DIN 7991
- Type
- Socket countersunk head screw
- Size
- M4 × 8
- Thread
- M4 × 0.7
- Length L
- 8 mm
- Socket size s
- 2.5 mm
- Head diameter dk
- 8 mm
- Head height k
- 2.48 mm
- Thread length b
- 20 mm
- Drive
- Hexagon socket
- Head
- Countersunk head (90°)
Nominal values in millimetres as published in DIN 7991. Estimated weight 1.36 g per piece in steel (1.369 g in stainless), calculated from the nominal geometry — real parts vary with tolerance and head chamfers.
Thread data
Full M4 thread pageDesignationM4 × 0.7
Pitch0.7 mm
Major Ø4 mm
Pitch Ø3.55 mm
Minor Ø ext3.14 mm
Tap drillØ 3.3 mm
Other lengthsDIN 7991 M4
All M4 specificationsInterchangeability
DIN 7991 is catalogued with ISO 10642 as its equivalent designation. Dimensions are compared field by field rather than assumed identical.