CO2 Detector WiFi Air Quality Monitor Temperature Humidity Tester Thermometer Hygrometer for Home Item Type: CO2 Detector Carbon Dioxide Detection: NDIR Smart APP Control: WiFi for TUYA app, which transfers data to mobile phones, supports for Android and for IOS phones, and also supports various languages. Carbon Dioxide Detection Range: 400-5000PPM CO2 Alarm Value: 1000PPM CO2 Alarm On and Off Function: If the you do not like the alarm, press the power button once to turn it off. Detection Temperature: -10℃ ~ 50℃ Detection Humidity: 20% - 85%RH Storage Temperature: -10℃ ~ 60℃ Battery: 1 x 800mAh rechargeable lithium battery, shipped with built in battery. Design: Cube shaped with lovely LED light design. Color Changes of Different Carbon Dioxide Values: Air Quality Level: Good CO2 Concentration: 400-1000PPM Led Color: Green Air Quality Level: Ok CO2 Concentration: 1001-2000PPM LED Color: Yellow Air Quality Level: Poor CO2 Concentration: 2001-5000PPM LED Color: red