Size

Pitch ofthread

Width across flats

Width across corners

Diameter of washer face

Depth of washer face

Thickness of nut

d

p

s

e

dw

c

m

Diameter

coarse pitch series

max.

min.

min.

min.

max.

max.

min.

M12

1.75

22

21.16

23.91

20.1

0.8

10.8

10.37

M16

2

27

26.16

29.56

24.9

0.8

14.8

14.1

M20

2.5

32

31

35.03

29.5

0.8

18

16.9

M22

2.5

36

35

39.55

33.3

0.8

19.4

18.1

M24

3

41

40

45.2

38

0.8

21.5

20.2

M27

3

46

45

50.85

42.8

0.8

23.8

22.5

M30

3.5

50

49

55.37

46.6

0.8

25.6

24.3

M36

4

60

58.8

66.44

55.9

0.8

31

29.4