Size Conversion Chart

Sue (AU & UK, NZ) US & Canada Circumference (mm)  Inside Diameter (mm)
H 4 46.80 14.88
H½ 4.25 47.40 15.09
I 4.5 48.00 15.29
J 4.75 48.70 15.49
J½ 5 49.30 15.70
K 5.25 50.00 15.90
K½ 5.5 50.60 16.10
L 5.75 51.20 16.31
L½ 6 51.90 16.51
M 6.25 52.50 16.71
M½ 6.5 53.10 16.92
N 6.75 53.80 17.12
N½ 7 54.40 17.32
O 7.25 55.10 17.53
O½ 7.5 55.70 17.73
P 7.75 56.30 17.93
P½ 8 57.00 18.14
Q 8.25 57.60 18.34
Q½ 8.5 58.30 18.54
R 8.75 58.90 18.75
R½ 9 59.50 18.95
S 9.25 60.20 19.15
S½ 9.5 60.80 19.35
T 9.75 61.40 19.56
T½ 10 62.10 19.76
U 10.25 62.70 19.96
U½ 10.5 63.40 20.17
V 10.75 64.00 20.37
V½ 11 64.60 20.57
W 11.25 65.30 20.78
W½ 11.5 65.90 20.93
X 11.75 66.60 21.18
X½ 12 67.20 21.39
Y 12.25 67.80 21.59
Y½ 		12.5 68.50 21.79
Z		 12.75 69.10 22.00
Z½ 		13 69.70 22.20
Z1 13.25 70.40 22.40
13.5 71.00 22.61
Z2 13.75 71.70 22.81
Z3 14 72.30 23.01
14.25 72.90 23.22
Z4 14.5 73.60 23.42