ISOscrewsCountersunk head (90°)

ISO 10642 Hexagon Socket Countersunk Head Screw

ISO equivalent of DIN 7991. Both use the same 90° countersink angle, so mating holes are interchangeable.

ISO 10642 M10 × 20 — Countersunk head (90°)Nominal dimensions in mm · Not to scale

Dimensions11 sizes · millimetres

Thread d	Pitch P (mm)	Head diameter dk (mm)	Head height k (mm)	Socket size s (mm)	Thread length b (min) (mm)
M3	0.5	6	1.86	2	18
M4	0.7	8	2.48	2.5	20
M5	0.8	10	3.1	3	22
M6	1	12	3.72	4	24
M8	1.25	16	4.96	5	28
M10	1.5	20	6.2	6	32
M12	1.75	24	7.44	8	36
M14	2	27	8.4	10	40
M16	2	30	8.8	12	44
M18	2.5	33	10.2	14	48
M20	2.5	36	11	14	52

Nominal dimensions in millimetres as published in ISO 10642. Tolerances, material requirements and marking are defined separately by the issuing body.

Available sizeslinked to individual specification pages

M3 × 6 M3 × 8 M3 × 10 M3 × 12 M3 × 16 M3 × 20 M3 × 25 M3 × 30

M4 × 6 M4 × 8 M4 × 10 M4 × 12 M4 × 16 M4 × 20 M4 × 25 M4 × 30 M4 × 40

M5 × 8 M5 × 10 M5 × 12 M5 × 16 M5 × 20 M5 × 25 M5 × 30 M5 × 40 M5 × 50

M6

M6 × 10 M6 × 12 M6 × 16 M6 × 20 M6 × 25 M6 × 30 M6 × 35 M6 × 40 M6 × 50 M6 × 60

M81.25 mm pitch

M8 × 12 M8 × 16 M8 × 20 M8 × 25 M8 × 30 M8 × 35 M8 × 40 M8 × 50 M8 × 60 M8 × 80

M101.5 mm pitch

M10 × 16 M10 × 20 M10 × 25 M10 × 30 M10 × 35 M10 × 40 M10 × 50 M10 × 60 M10 × 80 M10 × 100

M121.75 mm pitch

M12 × 20 M12 × 25 M12 × 30 M12 × 35 M12 × 40 M12 × 50 M12 × 60 M12 × 80 M12 × 100

M14

M14 × 25 M14 × 30 M14 × 35 M14 × 40 M14 × 50 M14 × 60 M14 × 80 M14 × 100

M16

M16 × 25 M16 × 30 M16 × 35 M16 × 40 M16 × 50 M16 × 60 M16 × 80 M16 × 100

M182.5 mm pitch

M18 × 30 M18 × 35 M18 × 40 M18 × 50 M18 × 60 M18 × 80 M18 × 100

M202.5 mm pitch

M20 × 30 M20 × 35 M20 × 40 M20 × 50 M20 × 60 M20 × 80 M20 × 100

Thread referencesused by the sizes above

M3 × 0.5 M4 × 0.7 M5 × 0.8 M8 × 1.25 M10 × 1.5 M12 × 1.75 M18 × 2.5 M20 × 2.5