The oxygen concentrator is intended for individual use in the home. It is an electronically operated device that separates oxygen from room air. It provides a high concentration of oxygen directly to you through a nasal cannula. Clinical studies have documented that oxygen concentrators are therapeutically equivalent to other types of oxygen delivery systems. Characters: Complete plastic out shell, safe and reliable. Timing accumulates function, shows total operating hours through the display screen Timing turns off function using convenience. Compressor pressure relief valves help the device safer. Power interruption alarm function.