Resistance Is Not Futile - Ohms Law - Electrician 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 Resistance Is Not Futile - Ohms Law - Electrician Shirt Resistance Is Not Futile shirt, ohms law shirt, electrician shirt Lightweight, Classic fit, Double-needle sleeve and bottom hem