Affordable oxygen machine Features1.the appearance of the patent, stylish appearance.2 Smaller, ... , better quality and more stable performance.Basic parameters1,Oxygen flow 0-3L/min Adjustable2,Oxygen concentration 2L 90±3% 3L ≥70%3 ... ,Outlet pressure of oxygen 50 KPa4,Operating noise ≤ 48dB (A)5,Timer Error ≤±0. ...