This boxer made of pure, non-irritating merino wool keeps you warm while providing superior comfort with flat seamsCombining merino wool with LIFA® Stay Warm fibers, this boxer HH® LIFA® Merino will provide warmth and comfort during your outdoor activities in cold weatherFiber Content: Shell: 57% Merino Wool, 43% PolypropyleneCare Instructions: Do not use fabric softener, do not try, use wool detergent, washWeight: 130g