This product uses the absorption principle of infrared light source (NDIR) to detect carbon dioxide gas in the on-site environment, and the 3.2-inch TFT color screen detects CO2 PM1.0、PM2.5、PM10、HCHO、TVOC、 Temperature, humidity, horn alarm, data recording 50000 sets of data exported to PDF and Excel documents, rechargeable lithium battery or separate external USB power supply (default English interface at the factory)