3 In 1 CO2 Monitor: Multi-functional carbon dioxide tester can detect carbon dioxide concentration in real time, monitor indoor and outdoor humidity and temperature. CO2 detection range. 400-5000PPM. temperature detection range. 0-50. Humidity detection range. 0-99%RH. Portable Air Quality Monitor: CO2 monitor has a built-in 1200 mAh rechargeable battery for 8 hours of continuous operation, it supports USB charging, and has a low battery indicator. mini CO2 detector is small, easy to carry, can be carried around as a decorative item, and can detect air quality anywhere, anytime. With intelligent warning system, high quality infrared NDIR sensor, multiple anti-interference. Mini CO2 Meter:With a sturdy hook that makes it easy to carry, it can be carried around as a decorative item, allowing you to monitor air quality anytime and anywhere. It can be used , office, school, travel, camping, RV, car, hotel, kitchen, bedroom, room, party, wine cellar, agriculture planting, indoor garden, grow room, etc. Clear LED Screen: The high definition LED screen allows you to read the data faster and easier. With 4 different color bars on the screen representing different CO2 levels (green, yellow, orange, red), it quickly identifies the quality of the air around you. This CO2 sensor only needs to be calibrated in a ventilated area for 5-10 minutes use, and then it is to start working. allow up to 35 seconds to respond to air quality changes. Accurate Measurement: If the CO2 in the air exceeds 1000 , people will feel uncomfortable and work/study less efficiently. In crowded , CO2 levels can rise and it is important to keep the room ventilated during viral periods. With CO2 detector, when the CO2 in the air exceeds 1200 , it will alert you in real time at a loud volume of 120 decibels for your safety, please open the windows in time to deal with this situation. color: White Material: ABS Package Contents: 1 set Indoor Air Quality Meters Only the above package content, other products are not included. Note: Light reflection 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.