I'm afraid that you regard the size as Euro Size and US Size.please do not follow system size chart !!!
if you want make a very correct choice you should choose by the size chart at the Second image !!!

>available: S，M， L， XL，2XL，3XL，4XL，5XL

>ASIA SIZE Shoulder / Chest / Length / Sleeve

S: 44cm/ 106cm/ 78.5cm/ 63cm
M: 45cm/ 110cm/ 80cm/ 64cm
L: 47cm/ 114cm/ 81.5cm/ 65cm
XL: 49cm/ 118cm/ 83cm/ 66cm
2XL: 50cm/ 122cm/ 84.5cm/ 67cm
3XL: 51cm/ 126cm/ 86cm/ 68cm
4XL: 52cm/ 130cm/ 87.5cm/ 69cm
5XL: 53cm/ 134cm/ 89cm/ 70cm