CY-12C Portable Oxygen Concentration Content Tester Meter Detector (Instructions are in English now) (Instructions are in English now) we sent the instructions to your email box This is a mini pocket tester. It is widely used for analyzing the purity of oxygen in respirator machine of medical treatment, anesthesia machine, oxygen concentrator, high-pressure oxygen house and nursing case for infant.It is comprised of oxygen sensor (oxygen electrode), secondary meters etc. It is light, firm and portable. Operating environment This oxygen detector is especially suitable to be used in such condition to detect the oxygen content. Detect the oxygen content in the environment of mines, vessels, chemical and chemical fertilizer industries. It is very efficient to prevent the explosion resulted from lack of oxygen when operating and is also efficient to keep the maintenance personnel smothering for lack of oxygen