Size Chart

Inner Diameter

 ES UK US EU China
14mm 4 F 3 44 4
14.6mm 6 G 3.75 45 6
15.3mm 8 I 4.5 47.5 8
16.0mm 10 K 5.5 50 9
16.6mm 12 L 6 52 11
17.2mm 14 N 6.75 54 13
17.8mm 16 P 7.25 56 15
18.4mm 18 Q 8 58 17
19.1mm 20 S 9 60 18