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， XXL

>ASIA SIZE Shoulder/ Chest/ Length/ Sleeve/
S: 43.5cm/ 104cm/ 63.5cm/ 62.5cm/
M: 45cm/ 108cm/ 65.5cm/ 64cm/
L: 46.5cm/ 112cm/ 67.5cm/ 65.5cm/
XL: 48cm/ 116cm/ 69.5cm/ 67cm/
XXL: 49.5cm/ 120cm/ 71.5cm/ 68.5cm/