SIZE CHART
| DIAMETER | US/CANADA | UK/AUSTRALIA |
|---|---|---|
| 15.7 mm | 5 | J 1/2 |
| 15.9 mm | 5.25 | K |
| 16.1 mm | 5.5 | K 1/2 |
| 16.3 mm | 5.75 | L |
| 16.5 mm | 6 | L 1/2 |
| 16.7 mm | 6.25 | M |
| 16.9 mm | 6.5 | M 1/2 |
| 17.1 mm | 6.75 | N |
| 17.3 mm | 7 | N 1/2 |
| 17.5 mm | 7.25 | O |
| 17.7 mm | 7.5 | O 1/2 |
| 17.9 mm | 7.75 | P |
| 18.1 mm | 8 | P 1/2 |
| 18.3 mm | 8 1/4 | Q |
| 18.5 mm | 8 1/2 | Q 1/2 |
| 18.7 mm | 8 3/4 | R |
| 18.9 mm | 9 | R 1/2 |
| 19.2 mm | 9.25 | S |
| 19.4 mm | 9.5 | S 1/2 |
| 19.6 mm | 9.75 | T |
| 19.8 mm | 10 | T 1/2 |
| 20 mm | 10.25 | U |
| 20.2 mm | 10.5 | U 1/2 |
| 20.4 mm | 10.75 | V |
| 20.6 mm | 11 | V 1/2 |
| 20.8 mm | 11.25 | W |
| 21 mm | 11.5 | W 1/2 |
| 21.2 mm | 11.75 | X |
| 21.4 mm | 12 | X 1/2 |
| 21.6 mm | 12.25 | Y |
| 21.8 mm | 12.5 | Z |
| 22 mm | 12.75 | Z 1/2 |
| 22.2 mm | 13 |

