ELECTRONICHEATING PADS Heating Pads system compatible with any 5V/2A USB power supply from cellphone Charger, Cellphone Power bank , Car jump starter, Car phone charger, and others. (Battery not included.) WARM AND WIDE TEMPERATURE RANGEExtra heat from electronic heated pads can warm your body at chilly midnight when you are camping outdoor.If you feel hot, just simply lower the heating mode or turn it off.Do not need to prepare an expensive down sleeping bag which sometime too hot for summer. COMPATIBLE SIZE AND LIGHT WEIGHT198X61CM (6.5X3FT) fit with most of Adult sleeping bag. with compact carry bag it is easy to be packed and carried. DURABLE POLYESTER SHELL AND SOFT FLANNEL LININGWater proof Oxford shell and Soft flannel lining keep you warm and comfy. MULTIPLE APPLICATION,100% SATISFACTION GUARANTYHeated sleeping bag liner can also be used as Sofa seat cushion, heated blanket, Heated car seat cushion etc. Wonvin brand creations and products glow the essence of elegance and luxury.