Insert 3 AA batteries into battery box, close box and plug sock wire into battery box, switch to "ON" position. Secure battery box into pouch with velcro closure. Pull on socl, use the straps to wrap pouch around top of the sock. Switch to OFF position and remove batteries, when not in use. Unisex Design. Up to 5 Hours of Heat. Carbon Fiber Heating Element. One Touch Operation. 6 x AA batteries required, (not included).