1.8in1 Air Quality Tester: Measures PM1.0, PM2.5, PM10, CO2, TVOC, HCHO, temperature and humidity simultaneously, with WiFi connectivity for cloud data access. High Accuracy Sensors: Equipped with a high precision NDIR infrared CO2 sensor, particle sensor, semiconductor sensor, optical sensor and distance sensor. Delivers high sensitivity, strong interference resistance, stable performance and low power consumption. LCD Color Display: Large color LCD with automatic brightness adjustment based on ambient light for clear readability without glare. At power on you can switch the displayed content between HCHO and TVOC and PM2.5/PM10. Sleep Approach Wakeup: Screen automatically turns off to reduce energy use after inactivity while the sensor continues to transmit data to the cloud via WiFi. Real-time values are accessible in the APP. The unit includes a distance sensor; in the dormant state (30 seconds without sensing) you can disable this feature in the APP, and you can wake the screen by approaching or waving in front of the device. Use scenarios: - Home environment monitoring to maintain healthy air quality and comfortable living conditions. - Office or classroom ventilation management to support productivity and well being. - Renovation, new furniture or paint application where VOCs and HCHO may be present, enabling timely air quality assessment and control.