Usage Tips:[5 in 1 Function]: The multi-function air quality monitor takes care of your health and can be widely used in home, office, classroom, hotel, gym, greenhouse, warehouse, etc. [LCD Color Screen]: Displays CO2, CO2 index, HCHO (formaldehyde), TVOC, temperature, humidity and battery level. LCD color digital display for easy and clear reading even in dark environment. [Carbon Dioxide Tester]: Adopt semiconductor sensor, air convection detection, quickly and accurately detect CO2 concentration in living environment. [4-color indicator and alarm buzzer]: 0-799PPM (Green), 800-1199PPM (Yellow), 1200-1599PPM (Orange), 1600PPM and more (Red). The buzzer will alarm when the CO2 concentration is higher than 1500PPM. [Rechargeable Design]: Built-in 1200mAh rechargeable lithium battery for strong endurance. With USB Type-C interface for fast charging via power adapter, power bank, laptop, etc. Screen: LCD Digital Color Screen Voltage: 5V DC Detection Principle: Semiconductor Sensor CO2 Detection Range: 400-5000PPM CO2 Detection Sensitivity: 1PPM HCHO Detection Range: 0-0.6mg/m3 TVOC Detection Range: 0-2.0mg/m3 Temperature Measurement Range: 0-50℃ Temperature Measurement Accuracy: ±1℃ Humidity Measurement Range: 0~99% RH Humidity Measurement Accuracy: ±2% RH Charging Port: Type-C, 500mA Built-in Battery: 3.7V 1200mAh Lithium Battery size:90x70x35mm Material:ABS colour:Black / White Package Contents: 1 * Air Quality Analyzer 1 * USB Cable 1 * English manual Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.