Built with superior quality, exceptional comfort and effective heating elements. The Tri-Zone heating technology produces even warmth without the bulk of traditional winter wear. Use it as a mid-layer or over your favorite shirt. The 3 different heating elements cover the right and left chest as well as a larger heater built in to the mid-back area. The rechargeable lithium ion battery provides up to 5 hours of heating time per charge. The battery also has a built-in low battery warning. Perfect for snowmobiling, motorcycling, camping, or just plain walking around. The Venture battery powered vest is completely self contained so you wont have to wire anything to your machine. Additional replacement batteries and chargers available separately.