866.239.4315
US Size Diameter in Inches Diameter in MM Metric -MM British French German Japanese Swiss
0000 .390 9.91
00 .422 10.72
0 .454 11.53
1/2 .474 11.95 A
3/4 .482 12.18 A 1/2
1 .487 12.37 38.9 B 1
1 1/4 12.60 39.6 B 1/2
1 1/2 .503 12.78 40.2 C
1 3/4 13.00 40.8 C 1/2
2 .520 13.21 41.5 D 41 1/2 13 1/2 2 1 1/2
2 1/4 13.41 42.1 D 1/2
2 1/2 .536 13.61 42.7 E 42 3/4 13 3/4 3 2 3/4
2 3/4 13.83 43.4 E 1/2
3 .553 14.05 44.0 F 44 14 4 4
3 1/8 14.15 44.3 F 1/2
3 1/4 14.25 44.6
3 3/8 14.36 44.9 G 45 1/4 5 5 1/4
3 1/2 .569 14.45 45.2 14 1/2
3 5/8 14.56 45.6  G 1/2 6
3 3/4 14.65 45.9 H 46 1/2 6 1/2
4 .585 14.86 46.5 H 1/2 15 7
4 1/4 15.04 47.1 I  47 3/4 7 3/4
4 1/2 .601 15.27 47.8 I 1/2 15 1/4 8
4 5/8 15.40 48.1 J 49 15 1/2 9
4 3/4 15.53 48.4
5 .618 15.70 49.0 J 1/2 15 3/4 9
5 1/8 15.80 49.3 K 50 10
5 1/4 15.90 49.6
5 3/8 16.0 50.0 K 1/2 10
5 1/2 .634 16.10 50.3 L 51 3/4 16 11 3/4
5 3/4 16.30 50.9
5 7/8 16.41 51.3 L 1/2
6 .650 16.51 51.5 M 52 3/4 16 1/2 12 12 3/4
6 1/4 16.71 52.2 M 1/2
6 1/2 .666 16.92 52.8 N 54 17 13 14
6 3/4 17.13 53.4 N 1/2
7 .683 17.35 54.0 O 55 1/4 17 1/4 14 15 1/4
7 1/4 17.45 54.7 O 1/2
7 1/2 .699 17.75 55.3 P 56 1/2 17 3/4 15 16 1/2
7 3/4 17.97 55.9 P 1/2
8 .716 18.19 56.6 Q 57 3/4 18 16 17 3/4
8 1/4 18.35 57.2 Q 1/2
8 1/2 .732 18.53 57.8 18 1/2 17
8 5/8 18.61 58.4 R 59 19
8 3/4 18.69 58.4
8 7/8 18.80 59.0 R 1/2
9 .748 18.89 59.1 19 18
9 1/8 19.10 59.4 S 60 1/4 20 1/4
9 1/4 19.22 59.7
9 3/8 19.31 60.0 S 1/2
9 1/2 .764 19.41 60.3 19 1/2 19
9 5/8 19.51 60.6 T 61 1/2 21 1/2
9 3/4 19.62 60.9
10 .781 19.84 61.6 T 1/2 20 20
10 1/4 20.02 62.2 U 62 3/4 21 22 3/4
10 1/2 .797 20.20 62.8 U 1/2 20 1/4 22
10 5/8 20.32 63.1 V 63 23 3/4
10 3/4 20.44 63.5
11 .814 20.68 64.1 V 1/2 20 3/4 23
11 1/8 20.76 64.3 W 65 25
11 1/4 20.85 64.7
11 3/8 20.94 65.0 W 1/2
11 1/2 21.08 65.3 21 24
11 5/8 .830 21.18 65.7 X 66 1/4 26 1/4
11 3/4 21.24 66.0
11 7/8 21.30 66.3 X 1/2
12 .846 21.49 66.6 Y 67 1/2 21 1/4 25 27 1/2
12 1/4 21.69 67.2 Y 1/2
12 1/2 .862 21.89 67.9 Z 68 3/4 21 3/4 26 28 3/4
12 3/4 22.10 68.5 Z 1/2
13 .879 22.33 69.1 22 27