Invacare XPO2 Portable Oxygen Concentrator is extremely lightweight and ideal for users who require around the clock oxygen therapy and do not want to worry of ever running out of their oxygen supply. The machine is very versatile and offers five (5) different pulse dose delivery settings to satisfy all types of oxygen users. The concentrator comes with an AC adapter for home or office use, car adapter for travel, carry case and either a single internal battery for 2.5 hours of operational use or with a double battery for 5 hours of operational use. Approved by the FAA for use on most commercial airlines. Comes with a 5 year warranty.