[5 in 1 Function]: This multi-function air quality monitor helps maintain a healthy environment and is suitable for use in homes, offices, classrooms, hotels, gyms, greenhouses, warehouses, and more. [LCD Color Screen]: Displays CO2, CO2 index, HCHO (formaldehyde), TVOC, temperature, humidity, and battery level. The LCD color digital screen provides clear and easy-to-read results, even in low-light conditions. [Carbon Dioxide Tester]: Features a semiconductor sensor with air convection detection to quickly and accurately measure CO2 concentration in indoor environments. [4-Color Indicator and Alarm Buzzer]: Visual indicators show CO2 levels: 0799 PPM (Green), 8001199 PPM (Yellow), 12001599 PPM (Orange), and 1600 PPM or higher (Red). An audible alarm activates when CO2 levels exceed 1500 PPM. [Rechargeable Design]: Built-in 1200mAh rechargeable lithium battery ensures long-lasting performance. Equipped with a USB Type-C port for convenient charging via power adapter, power bank, or laptop. Screen: LCD Digital Color Screen Voltage: 5V DC Detection Principle: Semiconductor Sensor CO2 Detection Range: 4005000 PPM CO2 Detection Sensitivity: 1 PPM HCHO Detection Range: 00.6 mg/m TVOC Detection Range: 02.0 mg/m Temperature Measurement Range: 050C Temperature Measurement Accuracy: 1C Humidity Measurement Range: 099% RH Humidity Measurement Accuracy: 2% RH Charging Port: Type-C, 500mA Built-in Battery: 3.7V 1200mAh Lithium Battery Size: 90 x 70 x 35 mm Material: ABS Color: Black / White Package Contents: 1 x Air Quality Analyzer 1 x USB Cable 1 x English Manual Note: The package includes only the items listed above. Other accessories are not included. Note: Lighting and display settings may cause slight variations in the product's color as seen on screen. Measurement error allowance: 13 cm.