3 in 1 Carbon Dioxide Detector: For 3 functions, you can intuitively understand the quality of the air you breathe with air quality including CO2, temperature and humidityHigh precision: sensor module with TVOC sensor to accurately monitor carbon dioxide, highly recommended to use with a USB chargerVisualization: the CO2 monitor with display Intelligent color display shows an indicator light that changes color according to different degrees of carbon dioxide concentration, allows you to easily grasp the current status of carbon dioxide concentration in the airWide application: portable CO2 monitor with compact design suitable for monitoring air quality at home, schools, office buildings, hospitals, restaurants, shopping malls, factories, hotels, laboratories, etc. /li>Why you need it: Perfect gift for your Valentine's Day gifts for him/her/kids, with the air quality monitor you can definitely know what your environment is like and improve it according to the actual situation. Features: Dimensions: 7 x 3.6 x 8.9 cm. Detection range: 400-5000 ppm. Applicable temperature: 1-70C. Charging port: Type C. Operating voltage: 5 V. Battery capacity: 1200 HMA CO2 content indicator display: 0-799 ppm flashing green light. 800- 1199 ppm flashing yellow light. 1200-1599 ppm - Flashing orange light. 1600-1999 ppm flashing red light. More than 1999 ppm au- top of four flashing colors