| Inside Circumference (mm) | Inside Diameter (mm) | US Size | UK Size |
|---|---|---|---|
| 44.14 | 14.05 | 3 | F |
| 45.4 | 14.45 | 3 ½ | G ½ |
| 46.68 | 14.86 | 4 | H ½ |
| 47.97 | 15.27 | 4 ½ | I ½ |
| 49.32 | 15.7 | 5 | J ½ |
| 50.58 | 16.1 | 5 ½ | L |
| 51.87 | 16.92 | 6 | M |
| 53.16 | 17.35 | 6 ½ | N |
| 54.51 | 17.75 | 7 | O |
| 55.76 | 18.19 | 7 ½ | P |
| 57.15 | 18.65 | 8 | Q |
| 58.47 | 19.04 | 8 ½ | R |
| 59.34 | 19.41 | 9 | S |
| 60.98 | 19.84 | 9 ½ | S ¾ |
| 62.33 | 20.2 | 10 | T ½ |
| 63.46 | 20.68 | 10 ½ | U ½ |
| 64.97 | 21.08 | 11 | V |
| 66.22 | 21.49 | 11 ½ | W ½ |
| 67.51 | 21.89 | 12 | Y |
| 68.77 | 22.33 | 12 ½ | Z |
| 70.15 | 22.6 | 13 | Z + 1 |
| 71.00 | 22.69 | 13 ½ | Z + 1 ½ |
| 72.00 | 23.06 | 14 | Z + 2 |
| 74.00 | 23.6 | 15 | Z + 3 |