Inside Diameter | US | UK | Germany | France |
15.3 mm | 4.5 | I | 48 (15.3) | 48 |
15.6 mm | 5 | J | 49 (15.6) | 49.5 |
16.2 mm | 5.5 | K | 51 (16.2) | 50.5 |
16.6 mm | 6 | L | 52 (16.6) | 52 |
16.9 mm | 6.5 | M | 53 (16.9) | 53 |
17.2 mm | 7 | N | 54 (17.2) | 54.5 |
17.8 mm | 7.5 | O | 56 (17.8) | 55.5 |
18.1 mm | 8 | P | 57 (18.1) | 57 |
18.5 mm | 8.5 | Q | 58 (18.5) | 58 |
19.1 mm | 9 | R | 60 (19.1) | 59.5 |
19.4 mm | 9.5 | S | 61 (19.4) | 61 |
19.7 mm | 10 | T | 62 (19.7) | 62 |