pompeii3
regular| Inside Diameter (mm) | USA / Canadian Standard | British, Irish, Australian Equivalent |
|---|---|---|
| 14.9 | 4 | H |
| 15.3 | 4 1/2 | I |
| 15.7 | 5 | J 1/2 |
| 16.1 | 5 1/2 | K 1/2 |
| 16.5 | 6 | L 1/2 |
| 16.9 | 6 1/2 | M 1/2 |
| 17.3 | 7 | N 1/2 |
| 17.7 | 7 1/2 | O 1/2 |
| 18.1 | 8 | P 1/2 |
| 18.5 | 8 1/2 | Q 1/2 |
| 18.9 | 9 | R 1/2 |
| 19.4 | 9 1/2 | S 1/2 |
| 19.8 | 10 | T 1/2 |
| 20.2 | 10 1/2 | U 1/2 |
| 20.6 | 11 | V 1/2 |
| 21 | 11 1/2 | W 1/2 |
| 21.4 | 12 | X 1/2 |
All Sizes in Inches Unless Otherwise Stated