Heat your core. Keeping your torso insulated and warm, is the best thing you can do to keep your entire body warm. The FNDN scarf will give off constant heat for up to 4.5 hrs on a single charge. Made from an ultra-soft micro-fleece, the FNDN heated scarf is powered by a rechargeable 7V Li-ion battery that heats a large 32.5″ x 8″ surface area (overall scarf length is 62″). 3 heat settings are controlled by a simple push button. Rechargeable battery and wall charger are included. It takes about 2 hours for a full charge.