Official Teenager Tshirt Birthday 13 years old 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 Birthday Tshirt for Boys or Girls 13 year old birthday tshirt Teenager Thirteen 13 Birthday Gift Tshirt for Boys or Girls 13 years old Thirteenth Thirteen 13 Lightweight, Classic fit, Double-needle sleeve and bottom hem