9in1 Air Quality Tester: This detector can be used to test and display the concentration of HCHO, TVOC, CO2, PM2.5, PM10, C6H6, temperature and humidity at the same time. High Accurate Sensors: Uses high-precise semiconductor TVOC sensor, electrochemical CO sensor, infrared PM2.5 sensor, temperature and humidity sensor, with high sensitivity, superior inteerence resistance ability, stable working peormance, with low power consumption. Large Screen Display: This air quality monitor with a 4.8inch large screen display, you can the data is clearly visible and the screen is not dazzling. Cellphone APP Control: Search for APP in the application program, the device will enter the pairing state after the firsttime opening, and you can view the specific data on the APP after completing the connection. Strong Heat Dissipation: Hundreds of ventilation holes reserved on the housing not only accelerate the convection between the air and the machine, thereby realizing effective detection, but also provide a fine heat dissipation effect.