Oxygen Concentrator, 5LThe Dynarex Oxygen Concentrator is a supplemental oxygen device used to relieve breathing difficulties. Ideal for a variety of medical and homecare settings. The Dynarex Oxygen Concentrator supplies additional oxygen to individuals with difficulty breathing. Users can customize oxygen flow with the adjustable flow knob. Works in conjunction with easily attached nasal cannulas (5201 5207) that hook over the ears and under the nose for easy inhalation.