God Said Maxwell Equations and Then There Was Light T Shirt 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 God Said Maxwell Equations and Then There Was Light is a funny physics t-shirt is what every physics lover need. God Said Maxwell Equations and Then There Was Light is a shirt made to be fitted. If you want a looser fit, please order a size up. A funny physics t-shirt is what every physics lover need. Lightweight, Classic fit, Double-needle sleeve and bottom hem