Please refer to the US and Japanese size conversion chart.
No. (Mikoku = Japanese size) -- Straight (mm) ---------Circumference (mm)
4=7--------------------14.9----------------- 47.0
5=9--------------------15.7----------------- 49.0
6=No. 11-------------------16.5------------------52.0
7=Size 13-----------------17.4-----------------55.0
8=16-------------------18.2-----------------57.0
9=19-------------------19.0-----------------59.7
10=21--------------------19.8------------------62.5
11=24--------------------20.7-----------------64.9
12=26--------------------21.4-----------------67.7
13=28--------------------22.0-----------------69.0
There may be slight differences in size measurements. Thank you for your understanding.
The ring will be labeled with US size.
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