Diameters (mm) Japan sizes UK sizes US sizes French sizes Italian sizes German sizes
14.9 7 H 1/2 4 46 1/2 7 15
15.3 8 I 1/2 4.5 47 3/4 8 15 1/4
15.7 9 J 5 49 9.5 15 3/4
16.1 10 K 1/2 5.5 50 3/4 11 16
16.5 12 L 1/2 6 51 1/2 12 16 1/2
16.9 13 M 1/2 6.5 52 3/4 13.5 17
17.3 14 N 1/2 7 54 14.5 17 1/4
17.7 16 P 7.5 55 1/4 16 17 3/4
18.1 17 Q 8 56 3/4 17 18
18.5 19 R 8.5 58 19 18 1/2
18.9 20 S 9 59 1/4 20 19
19.4 21 T 9.5 60 3/4 21 19 1/2
19.8 22 U 10 61 3/4 22.5 20
20.2 24 V 10.5 62 3/4 24 20 1/4
20.6 25 W 11 64 1/4 25 20 3/4
21.0 26 W 3/4 11.5 66 26.5 21
21.4 28 Y 12 67 1/2 27.5 21 1/4
21.8 29 Z 12.5 68 29 21 3/4
22.2 30 Z+1 13 69 30 22