Radioactive Shirt - Funny Tshirt for Men, Boys and Kids Solid colors: 100% Cotton; Heather Grey: 90% Cotton, 10% Polyester; All Other Heathers: 50% Cotton, 50% Polyester Imported Machine wash cold with like colors, dry low heat Radioactive Shirt - Funny Tshirt for Man, Boys and Kids Radioactive symbol t shirt. Fantastic Gift for Friends, Family Members and Colleagues. Lightweight, Classic fit, Double-needle sleeve and bottom hem