Feature:1. Wide Application: Widely used in factories, homes, offices and public places so on.2. Easy To Use: Large screen LCD backlit display, which can be read in the dark, save your labor.3. Portable And Lightweight: Portable monitor, used to detect O2, temperature, ℃/℉ unit can be switched.4. Accurate Detection: Quick response to gas detector, sound and light alarm instructions.5. Electrochemical Principle Measurement: High measurement accuracy with battery indicator, alarm value setting, adjustable volume.Specification:Item Type: Oxygen DetectorMaterial: ABSModel: AR8100Battery: Lithium battery 3.7V 1000mAh (built in battery)Uses: Widely used in factories, homes, offices and public places.Support Language: EnglishAlarm: Audio and lightWorking Time:> 90hWorking Temperature: -10-50℃Measuring Range: 0~25%Resolution: 0.1%Accuracy: 23.5% oxygen enriched20.96% normal19.5% minimum15~19% reduces efficiency, causing problems in the head, lungs and circulatory system10~12% Shortness of breath, loss of judgment, purple lips8~10% treatment failed, syncope, coma, pale face, nausea and vomiting6~8% 8 minutes, low blood pressure, rapid heartbeat, mouth breathing, stop breathing quickly4~6% 40 seconds, convulsions, respiratory arrest, death