Mens Joe Boxer Fall / Winter Reversible Thermal Sleepwear / Pajama Pants - Grey & Black Extremely high quality fabric: 55% polyester, 45% cotton; Machine washable. 100% authentic Joe Boxer merchandise....Very high quality mens sleepwear - satisfaction guaranteed! Fabric covered elastic waistband with drawstring ensures a comfortably snug fit. Legs are cut full and loose, relaxed styling provides a comfortable and casual fit.