Desktop USB Heated Coffee / Tea Mug Warmer Coffee Cup Warm Sleeve USB powered, no batteries required, easy to tote and take anywhere Use for coffee, tea, hot cocoa & more Keep beverage warm The Coffee or tea warm at 113- 122 Fahrenheit (45-50 degrees C) Wrap the warmer around your mug and plug in the usb cord to your lap top or in car with usb adapter. The cord is about 4 feet in length and the sleeve wraps around and has velcro to hold it together