Until now, oxygen concentrators have been very similar - heavy, bulky, noisy, or requiring frequent maintenance. EverFlo from Respironics is a unique stationary concentrator that delivers what homecare providers want and patients deserve. Features Lightweight for easy transport The EverFlo Oxygen concentrator weighs in at only 31 pounds, reducing shipping and storage costs and risk of injury. Compact design looks less like a medical machine EverFlo's ergonomic design takes up less space and doesn't draw as much attention. The Right Fit series focuses on patients' needs EverFlo is part of the Right Fit, a complete portfolio of oxygen products and programs inspired by patients and built for business. Low maintenance for reduced service costs No homecare provider filter change for two years. Patients do not ever have to change filters. Lower power consumption makes EverFlo patient-friendly The system uses less electricity and produces less heat. Humidifier Bottle Platform for extra flexibility The platform is designed to be compatible with all bottle styles and features an easy-to-use closure. Recessed flow meter reduces accidental breakage Oxygen purity indicator option for increased security EverFlo is available with or without oxygen purity indicator. This OPI (Oxygen Percentage Indicator) ultrasonically measures oxygen output as a purity.