DIAMETER (mm)

14.1

14.3

14.5

14.7

14.9

15.1

15.3

15.5

15.7

15.9

16.1

16.3

16.5

16.7

16.9

17.1

17.3

17.5

17.7

17.9

18.1

18.2

18.3

18.5

18.8

19.0

19.2

19.4

EUROPE

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

UK & AUSTRALIA

F 1/2

G

G 1/2

H

H 1/2

I

I 1/2

J

J 1/2

K

K 1/2

L

L 1/2

M

M 1/2

N

N 1/2

O

O 1/2

P

P 1/2

Q

Q 1/2

R

R 1/2

S

S 1/2

US & CANADA 

3

3 1/2

4

4 1/2

5

5 1/2

6

6 1/2

7

7 1/2

8

8 1/2

9

9 1/2