Keep calm and let the Microbiologist handle it 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 Keep calm and let the Microbiologist handle it Keep calm and let the Microbiologist handle it Shirt Lightweight, Classic fit, Double-needle sleeve and bottom hem