Koson-Man Men's Lace-up Sports Swimming Underwear Briefs Trunks polyester Material of the trunks:Nylon and Polyurethane.The trunks made of about 82% Nylon/Polyester,18% Polyurethane. The trunks's size:Size (S) Waist = 68-76cm Size (M) Waist = 64-73cm Size (L) Waist = 77-84cm Size (XL) Waist = 84-94cm Because the soft material,The trunks wear very comfortable and also breathable. The trunks were designed by our designer, they do their best to design out the fashionable style.They fit to summer beach. The trunks' are Asian size, Please order one size up than your normally wear.