Gears Gen X-3 Warm Tek Heated Vest - 38 Windproof, waterproof polyester main body construction for maximum warmth Entire Vest is heated, including the back and collar Features two front side pockets Connects to 12V power source; 20in. battery cord included Size 34 provides 35W of heat and draws 2.9A; sizes 36-52 provide 45W of heat and draw 3.7A; sizes 54-56 provide 71W of heat and draw 5.9A