SIZE UK | SIZE US | CIRCUMFERENCE (MM) | DIAMETER (MM) |
H | 4 1/4 | 46.8 | 14.88 |
I | 4 3/4 | 48.0 | 15.29 |
J | 5 1/4 | 48.7 | 15.49 |
K | 5 1/2 | 50.0 | 15.9 |
L | 6 | 51.2 | 16.31 |
M | 6 1/2 | 52.5 | 16.71 |
N | 7 | 53.8 | 17.12 |
O | 7 1/2 | 55.1 | 17.53 |
P | 8 | 56.3 | 17.93 |
Q | 8 1/2 | 57.6 | 18.34 |
R | 8 3/4 | 58.9 | 18.75 |