The Mobile Warming Unisex Peak BT Heated Vest is constructed from Windshark, a comfortable 4-way stretch material softshell fabric that offers comfort, flexibility, and protection from rain, water, and wind. There is also a polyester moisture wicking mest liner. The mid-weight Peak BT Heated vest is thick enough to be worn as your outer layer and thin enough to be used under a larger ski jacket or heavy work coat. It has integrated, concealed heating panels powered by a sturdy yet light-weight 7.4volt Far-Infrared Heating System. There are three heating elements, one on the upper back and two on the chest, that add heat to critical areas to keep your core warm. It can provide temperatures ranging from 135°F on high to 90°F on low. On high, expect up to 2.5 hours of heat, and on low, for up to 10 hours. The Peak BT has two ways to adjust the temperature. First, the built-in touch control button. With a simple button push, you can select from four heat settings. Second, you can have Bluetooth control with a MW ConnectTM app. Through the MW ConnectTM app, you can adjust individual heat levels to your liking. MW ConnectTM allows you to get real-time updates on battery levels and update your garments when new firmware becomes available. Includes the 7.4V (2200 mAh) Lithium-Ion Battery and a micro USB charging cable. You can expect up to 10 hours of power per charge.