Our indoor Solar Window Heater uses new technology to heat the air and warm the room for free. This technology will help lower your heating bill during the coming winter, and all without any installation. Easy setup includes the simple process of placing the unit next to south faced window so that the collector stands next to the window inside the room and the inlet and outlet will face the room. The inlet will suck the air from the room, circulate it inside the collector, and the outlet will send it back to the room at a higher temperature in order to warm the room. The unit comes with a 12v adapter to supply power to the fan in order to circulate the air. You can use the unit in cars, RVs, boats, etc. as the unit has a standard 12v inlet The digital temperature display will let you know the temperature that the collector is generating. Free shipping, and ships within 7 Business days of order