I ordered these boxers a size up, I am medium (36 in waste). Their chart suggests L, I ordered XL and they fit perfectly. I am already used to Asian sizes that run much smaller than US sizes. This is causing many bad reviews to some of their sized clothing charts which I suggest being revised. The description tag is in Chinese but I assume that the briefs are made of 95% cotton and 5% polyester or rayon (judging by the softness and feel or look of the material). The waist band I assume is made of 90% Spandex and 10% Rayon (or viceversa), which I recommend to be in English if selling in the US market. To be fair I slashed only a star in spite of all these details because I love their fit, softness and style. They are very soft and comfortable.