| U.S. | "Metric" | "U.K." |
| 0 | "2.0mm" | "14" |
| 6 | "4.25mm" | "/" |
| 7 | "4.5mm" | "7" |
| 8 | "5mm" | "6" |
| 9 | "5.5mm" | "5" |
| 10 | "6mm" | "4" |
| 10.5 | "6.5mm" | "3" |
| n/a | "7mm" | "2" |
| n/a | "7.5mm" | "1" |
| 11 | "8mm" | "0" |
| 13 | "9mm" | "00" |
| 1 | "2.25mm" | "13" |
| 15 | "10mm" | "000" |
| 17 | "12mm" | "/" |
| 19 | "15mm" | "/" |
| 35 | "20mm" | "/" |
| n/a | "2.5mm" | "/" |
| n/a | "2.75mm" | "12" |
| n/a | "3.0mm" | "11" |
| 3 | "3.25mm" | "10" |
| 4 | "3.5mm" | "/" |
| 5 | "3.75mm" | "9" |
| n/a | "4mm" | "8" |