Inner Diameter (mm)

Inner Diameter (Inches)

India

Europe

UK, Australia & South Africa

United States & Canada

China

Singapore & Japan

Hong Kong

14.01

0.55

4

44

F½

3

6

4

6

14.33

0.56

5

45

G

5

14.5

0.57

G½

3½

7

7.5

14.65

0.58

6

46

H

6

14.97

0.59

7

47

H½

4

8

7

9

15.1

0.59

I

9

15.29

0.60

8

48

I½

4½

8

10

15.5

0.61

J

15.61

0.61

9

49

J½

5

10

9

11

15.92

0.63

10

50

K

16.1

0.63

K½

5½

11

10

12

16.24

0.64

11

51

L

16.56

0.65

12

52

L½

6

12

11

13

16.7

0.66

M

13

12

16.88

0.66

13

53

M½

6½

13

14.5

17.1

0.67

N

14

17.2

0.68

14

54

N½

7

14

16

17.52

0.69

15

55

O

15

17.7

0.70

O½

7½

15

17

17.83

0.70

16

56

P

16

18.15

0.71

17

57

P½

8

17

16

18.2

0.72

18

18.3

0.72

Q

18.47

0.73

18

58

Q½

8½

18

17

19

18.79

0.74

19

59

R

19.0

0.75

R½

9

19

18

20.5

19.11

0.75

20

60

S

20

19.43

0.76

21

61

S½

9 ½

19

22

19.6

0.77

T

21

19.75

0.78

22

62

T½

10

20

23

20.0

0.79

23

U

22

21

20.06

0.79

24

63

U½

10½

22

24

20.38

0.80

64

V

23

20.6

0.81

25

V½

11

23

25

20.70

0.81

65

W

24

21.02

0.83

26

66

W½

11½

25

24

26

21.2

0.83

X

21.34

0.84

27

67

X½

12

26

25

27.75

21.6

0.85

28

Y

21.66

0.85

68

Z

12½

26

21.97

0.86

29

69

Z½

22.29

0.88

30

70

13

27

30

22.4

0.88

Z+1

22.61

0.89

31

71

Z+2

13½

22.9

0.90

32

23.2

0.91

33

23.5

0.93

34

23.9

0.94

35

24.2

0.95

36