Baby Buns Boys' Wave Rider Rashguard Swimwear Set Rashguard: 92% Polyester, 8% Spandex; Swimtrunk: 100% Polyester Imported Machine Wash Rashguard is 92 percent polyester and 8 percent spandex and the swim trunk is 100 percent polyester 2 piece wave rider surfs up rashguard and trunk set