All of the rings in the store are referenced with both the international UK (A-Z) measurement. Please use the table below for references:
| Inner Circumference (MM) | Inside Diameter (MM) | NZ, AUSTRALIA, UK & EU | ASIA |
| 45.5 | 14.5 | G | 4 ½ |
| 46.1 | 14.7 | G ½ | |
| 46.8 | 14.9 | H | 4 |
| 47.4 | 15.1 | H ½ | |
| 48.0 | 15.3 | I | 4 ½ |
| 48.7 | 15.5 | J | |
| 49.3 | 15.7 | J ½ | 5 |
| 50.0 | 15.9 | K | |
| 50.6 | 16.1 | K ½ | 5 ½ |
| 51.2 | 16.3 | L | |
| 51.9 | 16.5 | L ½ | 6 |
| 52.5 | 16.7 | M | |
| 53.1 | 16.9 | M ½ | 6 ½ |
| 53.8 | 17.1 | N | |
| 54.4 | 17.3 | N ½ | 7 |
| 55.1 | 17.5 | O | |
| 55.7 | 17.7 | O ½ | 7 ½ |
| 56.3 | 17.9 | P | |
| 57.0 | 18.1 | P ½ | 8 |
| 57.6 | 18.3 | Q | |
| 58.3 | 18.5 | Q ½ | 8 ½ |
| 58.9 | 18.8 | R | |
| 59.5 | 19.0 | R ½ | 9 |
| 60.2 | 19.2 | S | |
| 60.8 | 19.4 | S ½ | 9½ |
| 61.4 | 19.6 | T | |
| 62.1 | 19.8 | T ½ | 10 |
| 62.7 | 20.0 | U | |
| 63.4 | 20.2 | U ½ | 10 ½ |
| 64.0 | 20.4 | V | |
| 64.6 | 20.6 | V ½ | 11 |
| 65.3 | 20.8 | W | |
| 65.9 | 21.0 | W ½ | 11 ½ |
| 66.6 | 21.2 | X | |
| 67.2 | 21.4 | X ½ | 12 |
| 67.8 | 21.6 | Y | |
| 68.5 | 21.8 | Z | 12 ½ |
| 69.1 | 22.0 | Z ½ | |
| 69.7 | 22.2 | 13 | |
| 70.4 | 22.4 | Z +1 |