Size Guide

Inside

Diameter

(in)
Inside

Diameter

(mm)

Inside

Circumference

(in)

Inside

Circumference

(mm)

USA and

Canada

UK , Ireland

and Australia

Japan and

China

Switzerland
0.458 11.63 1.44 36.5 0 - - -
0.466 11.84 1.46 37.2 1/4 - - -
0.474 12.04 1.49 37.8 1/2 A - -
0.482 12.24 1.51 38.5 3/4 A 1/2 - -
0.49 12.45 1.54 39.1 1 B 1 -
0.498 12.65 1.56 39.7 1 1/4 B 1/2 - -
0.506 12.85 1.59 40.4 1 1/2 C - -
0.514 13.06 1.61 41.0 1 3/4 C 1/2 - -
0.522 13.26 1.64 41.7 2 D 2 1.5
0.53 13.46 1.67 42.3 2 1/4 D 1/2 - -
0.538 13.67 1.69 42.9 2 1/2 E 3 2.75
0.546 13.87 1.72 43.6 2 3/4 E 1/2 - -
0.554 14.07 1.74 44.2 3 F 4 4
0.562 14.27 1.77 44.8 3 1/4 F 1/2 5 5.25
0.57 14.48 1.79 45.5 3 1/2 G - -
0.578 14.68 1.82 46.1 3 3/4 G 1/2 6 6.5
0.586 14.88 1.84 46.8 4 H 7 -
0.594 15.09 1.87 47.4 4 1/4 H 1/2 - 7.75
0.602 15.29 1.89 48.0 4 1/2 I 8 -
0.61 15.49 1.92 48.7 4 3/4 J - 9
0.618 15.70 1.94 49.3 5 J 1/2 9 -
0.626 15.90 1.97 50.0 5 1/4 K - 10
0.634 16.10 1.99 50.6 5 1/2 K 1/2 10 -
0.642 16.31 2.02 51.2 5 3/4 L - 11.75
0.65 16.51 2.04 51.9 6 L 1/2 11 12.75
0.658 16.71 2.07 52.5 6 1/4 M 12 -
0.666 16.92 2.09 53.1 6 1/2 M 1/2 13 14
0.674 17.12 2.12 53.8 6 3/4 N - -
0.682 17.32 2.14 54.4 7 N 1/2 14 15.25
0.69 17.53 2.17 55.1 7 1/4 O - -
0.698 17.73 2.19 55.7 7 1/2 O 1/2 15 16.5
0.706 17.93 2.22 56.3 7 3/4 P - -
0.714 18.14 2.24 57.0 8 P 1/2 16 17.75
0.722 18.34 2.27 57.6 8 1/4 Q - -
0.73 18.54 2.29 58.3 8 1/2 Q 1/2 17 -
0.738 18.75 2.32 58.9 8 3/4 R - 19
0.746 18.95 2.34 59.5 9 R 1/2 18 -
0.754 19.15 2.37 60.2 9 1/4 S - 20.25
0.762 19.35 2.39 60.8 9 1/2 S 1/2 19 -
0.77 19.56 2.42 61.4 9 3/4 T - 21.5
0.778 19.76 2.44 62.1 10 T 1/2 20 -
0.786 19.96 2.47 62.7 10 1/4 U 21 -
0.794 20.17 2.49 63.4 10 1/2 U 1/2 22 22.75
0.802 20.37 2.52 64.0 10 3/4 V - -
0.81 20.57 2.54 64.6 11 V 1/2 23 -
0.818 20.78 2.57 65.3 11 1/4 W - 25
0.826 20.98 2.59 65.9 11 1/2 W 1/2 24 -
0.834 21.18 2.62 66.6 11 3/4 X - -
0.842 21.39 2.65 67.2 12 X 1/2 25 27.5
0.85 21.59 2.67 67.8 12 1/4 Y - -
0.858 21.79 2.70 68.5 12 1/2 Z 26 28.75
0,866 22.00 2.72 69.1 12 3/4 Z 1/2 - -
0.874 22.20 2.75 69.7 13 - 27 -
0.882 22.40 2.77 70.4 13 1/4 Z1 - -
0.89 22.61 2.80 71.0 13 1/2 - - -
0.898 22.81 2.82 71.7 13 3/4 Z2 - -
0.906 23.01 2.85 72.3 14 Z3 - -
0.914 23.22 2.87 72.9 14 1/4 - - -
0.922 23.42 2.90 73.6 14 1/2 Z4 - -
0.93 23.62 2.92 74.2 14 3/4 - - -
0.938 23.83 2.95 74.8 15 - - -
0.948 24.03 2.97 75.5 15 1/4 - - -
0.954 24.23 3.00 76.1 15 1/2 - - -
0.962 24.43 3.02 76.8 15 3/4 - - -
0.97 24.64 3.05 77.4 16 - - -