... three CO2 3)Withsuper large capability memorizer 4)School CO2 monitor with data logger A, Feature:Real-time monitoring carbon dioxide (CO2 ... from 0 to 100%RHNon-dispersive infrared (NDIR) CO2 sensor with self calibration, 15 years lifetimeThe 3-LED indicator lights indicate ... any USB disk, and copy the data to a PC B, Application:Used in schools, kindergartens, office buildings, greenhouses and so ...