We maintain a large inventory of gently used oxygen concentrators for sale, including the Inogen One, SeQual Eclipse, Respironics Evergo, Invacare XPO2, and many other home and portable oxygen concentrators. Our inventory changes often, so please call us for a current listing of used oxygen concentrators for sale. Used oxygen concentrators used to have a reputation for being unreliable, but with our rigorous testing and refurbishing, we assure the highest quality.