Thread
designation

Diameter

inches

Outside
diameter
mm

Nut
diameter
mm

Tap hole
diameter
mm

Turns per
inch

G 1/8"

 1/8

9.73

8.85

8.8

28

G 1/4"

 1/4

13.16

11.89

11.8

19

G 3/8"

 3/8

16.66

15.39

15.25

19

G 1/2"

 1/2

20.95

19.17

19

14

G 3/4"

 3/4

26.44

24.66

24.5

14

G 1"

1

33.25

30.93

30.75

11

G 1 1/4"

1 1/4

41.91

35.59

39.25

11

G 1 1/2"

1 1/2

47.8

45.48

45.25

11

G 2"

2

59.61

57.29

57

11