Great for winter sports, spectator sports, hunting, or hiking, or all of the above! Nordic Gear Battery-Heated Lectra-Sox provide hours of maintained warmth for your feet. High-tech Holofil fibers wick moisture away from the skin to keep feet dry and prevent overheating. Plus, you don't have to worry about getting shocked - Lectra-Sox are designed to be safe even when wet. A recessed channel built into the leg and toe area keeps the heating unit flush with the sock for added comfort. The accessible battery pouch ensures easy heat control and added cushioning in the sole. The snap on/off control allows for easy, one-handed operation. Each sock requires 1 D-cell battery, which delivers 2 to 3 hours of reliable warmth (batteries not included). Made from a 36\\% virgin wool, 33\\% winter acrylic, 22\\% polyester, 9\\% nylon fabric blend.