Respironics Evergo Portable 02 Concentrator U900-000-02

The EverGo's 8-hour average battery life, 1050 ml per minute oxygen capacity, lightweight non-medical design (weighs less than 10 pounds), and easy-to-use touch screen mean you can finally be active all day.

Other portable concentrator units can provide a maximum of 500–750 ml/min of oxygen. But EverGo delivers 1,050 ml/min of oxygen through fixed bolus delivery, increasing the amount of oxygen with each setting.