Santonis Men's Low Rise Skinny Modal Boxer Brief Red 5% spandex 95% Chinlon and 5% Spandex Waist: US XS=China S:26"-29"; US S=China M:30"-32"; US M=China L:33"-35"; US L=China XL:35"-37" It is good to reduce the stimulation to the skin Feels extremely light against your skin You select size is US Size,but we send product tag size is China Size.The China Size is bigger one size than you order.Because of the China size is about 1 size smaller than US size.And our company product tag is printed in China size only.For example,you order size "M", we will send you the item with China label size "L".Thanks!