| A | B | |
|---|---|---|
1 | Ring Diameter (MM) | USA/Canada |
2 | 14.0 mm. | 3 |
3 | 14.4 mm. | 3½ |
4 | 14.8 mm. | 4 |
5 | 15.2 mm. | 4½ |
6 | 15.6 mm. | 5 |
7 | 16.0 mm. | 5½ |
8 | 16.5 mm. | 6 |
9 | 16.9 mm. | 6½ |
10 | 17.3 mm. | 7 |
11 | 17.7 mm. | 7½ |
12 | 18.2 mm. | 8 |
13 | 18.6 mm. | 8½ |
14 | 19.0 mm. | 9 |
15 | 19.4 mm. | 9½ |
16 | 19.8 mm. | 10 |
17 | 20.2 mm. | 10½ |
18 | 20.6 mm. | 11 |
19 | 21.0 mm. | 11½ |
20 | 21.4 mm. | 12 |
21 | 21.8 mm. | 12½ |
22 | 22.2 mm. | 13 |
23 | 22.6 mm. | 13½ |