Gears Canada Gen X-3 Warm Tek Heated Jacket Liner , Gender: Mens/Unisex, Primary Color: Black, Size: Md Windproof, waterproof polyester main body construction for maximum warmth Side panel features dual-layer construction; Lycra (inner) and breathable cotton/Lycra blend (outer) allows moisture to escape while retaining heat and a snug fit Entire liner is heated, including the back and collar Mens jacket features an external zippered pocket on the front chest; womens jacket features two front side pockets and a female-specific tapered fit Connects to 12V power source; 20in. battery cord included