Size

1/4

5/16

3/8

7/16

1/2

9/16

5/8

3/4

7/8

1

Threads per inch

UNC

20

18

16

14

13

12

11

10

9

8

UNF

28

24

24

20

20

18

18

16

14

12

Width across flats

B inch

7/16

1/2

9/16

11/16

3/4

7/8

15/16

11/8

15/16

11/2

B mm

11.11

12.70

14.28

17.46

19.05

22.22

23.81

28.57

33.33

38.10

Thickness

H inch

7/32

17/64

21/64

3/8

7/16

31/64

35/64

41/64

3/4

55/64

H mm

5.55

6.74

8.33

9.52

11.11

12.30

13.89

16.27

19.05

21.82

Approx. weight

Kg/1000pcs.

3.2

4.7

6.8

12.6

16.9

26.5

33.8

56.9

86.4

133.2