An oxygen concentrator is a device that concentrates the oxygen from a gas supply by selectively removing nitrogen to supply an oxygen-enriched product gas stream. An oxygen concentrator uses that air then it comes out as 90 to 95 percent pure oxygen and 5 to 10 percent nitrogen. Are you looking the branding quality portable Oxygen Concentrator Manufacturers and suppliers from India? ATD Group is known as leading portable oxygen concentrator supplier in India. They have all sizes and types of portable oxygen ... Oxygen Concentration .