50% Polyester + 50% Cotton. This is elastic waist,so we recommend the waist range. This is Chinese size which is smaller than US/EU size. China Size M = US size XS. MODEL height 178cm 75kg wear size XXL. The size chart is for reference only. Due to different measure,may exsit 2-4 cm error,should be acceptable. In order to choose correct size,please contact our customer service. Our professinal customer service offers you suitable size advice.