DIN 7991 Flat Head Countersunk Socket

The difference between countersunk socket head screws and ordinary socket head screws is mainly reflected in the structure of the screw head.

Additional information

The difference between countersunk socket head screws and ordinary socket head screws is mainly reflected in the structure of the screw head.

All measurements in millimeters (mm)

d1	b	t	s	k max	d2
M3	12	1.2	2	1.7	6
M4	14	1.8	2.5	2.3	8
M5	16	2.3	3	2.8	10
M6	18	2.5	4	3.3	12
M8	22	3.5	5	4.4	16
M10	26	4.4	6	5.5	20
M12	30	4.6	8	6.5	24
M16	38	5.3	10	7.5	30
M20	46	5.9	12	8.5	36
M24	54	10.3	14	14	39

The difference between countersunk socket head screws and ordinary socket head screws is mainly reflected in the structure of the screw head. The screw head of the countersunk hexagon socket screw is conical. After installation, the screw head can be stuffed into the mounting surface to ensure the flatness of the mounting surface. The screw head of the ordinary hexagon socket screw is cylindrical. After installation, the screw head protrudes above the mounting surface. ‍