US Size
5
6
7
8
9
10
11
12
13
Inner Diameter (MM)
 15.7 16.5 17.3 18.1 18.9 19.8 20.6 21.4 22.4
Inner Circumference (MM)
 49.3 51.9 54.4 57 59.5 62.1 64.6 67.2 70.4

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