Features: 2.8-inch large screen simultaneously display the current CO2 concentration, temperature, humidity and time. WiFi smart CO2 tester supports to connect with the mobile phone to check the air quality data anytime anywhere. Equipped with high-quality temperature sensor and humidity sensor, which can detect quickly and accurately. Automatic refresh detection data, real-time monitoring, stable and reliable. 4pcs color light bar(green, yellow, orange, and red) indicate for the corresponding CO2 concentration. Two buttons control, convenient to switch the temperature unit between and , ON/OFF the detector, calibrate the data. Simple operation, no calibration after startup, automatic operation and detection. Small size, light weight, easy to carry. Compact portable size with simple modern appearance, suitable for home, office, dormitory, warehouse, etc. It helps you check the air condition and is a good helper for home inspection, greenhouse planting, warehouse carbon dioxide detection, etc Specifications: Material: ABS Power: 5V1A CO2 Sensor: 400-5000ppm Accuracy: (50ppm+5% reading value) Humidity Sensor: 0-100%RH Accuracy: 2%RH(25) Working Temperature: -10~50, 0~95%RH Communication Protocol: WiFi Item Size: 89 * 65 * 25mm / 3.50 * 2.56 * 0.98in Item Weight: 90g / 3.20oz Package Weight: 136g / 4.80oz Package Size: 9.3 * 8.8 * 3.1cm / 3.66 * 3.46 * 1.22in Package List: 1 * CO2 Detector 1 * USB Cable 1 * Manual (English)