Portable Oxygen Concentrator is exceptionally small and light making it ideal for those who require a unit they can travel with, who do not have much space for a concentrator, or who cannot carry a heavier unit. Add the optional Plug for Car DC Outlet / DC inverter kit and you can travel the country in your car, without the constant hassle and worry of a backseat full of oxygen tanks or having to get refills in every major city. Just plug the Portable Oxygen Concentrator into the DC inverter, turn it on, and you have a constant supply of oxygen in the car. It also can be provide the anion with one key switching.