Cross-reference Metric measurements with US letters and UK/Canadian numbers instantly.
| Metric Size | US Designation | UK / Canadian Number |
|---|---|---|
| 2.25 mm | B - 1 | 13 |
| 2.75 mm | C - 2 | 12 |
| 3.25 mm | D - 3 | 10 |
| 3.50 mm | E - 4 | 9 |
| 3.75 mm | F - 5 | 5 |
| 4.00 mm | G - 6 | 8 |
| 4.50 mm | 7 | 7 |
| 5.00 mm | H - 8 | 6 |
| 5.50 mm | I - 9 | 5 |
| 6.00 mm | J - 10 | 4 |
| 6.50 mm | K - 10.5 | 3 |
| 7.00 mm | — | 2 |
| 8.00 mm | L - 11 | 0 |
| 9.00 mm | M / N - 13 | 00 |
| 10.00 mm | N / P - 15 | 000 |
| 15.00 mm | P / Q | — |
| 16.00 mm | Q | — |
| 19.00 mm | S | — |
| 25.00 mm | U | — |