STEP 3 Use a ruler to measure the distance between the marks in mm
DIAMETER | CIRCUMFERENCE | SIZE |
14,9 mm | 48 mm | 4 |
15,7 mm | 49 mm | 5 |
16,5 mm | 52 mm | 6 |
17,3 mm | 54 mm | 7 |
18,2 mm | 56 mm | 8 |
19 mm | 59 mm | 9 |
19,2 mm | 62 mm | 10 |
20,6 mm | 64 mm | 11 |
21,4 mm | 67 mm | 12 |