This is a 10-in-1 Portable Smartair Quality Tester: Ultra-Precise Multi-Gas Detection Accurately monitors CO, CO2, HCHO (Formaldehyde), TVOC, Benzene, and PM2.5/PM10 with <±5% error. Wide detection range ensures reliable air quality assessment in homes, offices, or workshops. Air quality tester equipped with a high-definition color screen for real-time data display, making it clear and easy to read. It provides an overall assessment of environmental quality and tracks the average value of each gas, helping you quickly identify unsafe gases in the air. In alarm mode, the screen changes color to remind you to pay attention to the environment. Home air quality test built with high-performance chips sensor technology for CO2 detection, as well as electrochemical sensors for HCHO and TVOC. It is more sensitive, accurate, and stable compared to ordinary sensors. Air quality sensor press and hold the "Power" button for 3 seconds to turn the air quality monitor on or off. Once powered on, it automatically starts detecting. The default temperature unit is Celsius (℃), but you can switch to Fahrenheit (℉) by pressing and holding the "Power" button for 1 second. Air monitor equipped with a built-in 2000mAh rechargeable lithium battery and a USB charging cable, it can last up to 20 hours on a single charge. Its lightweight and portable design make it suitable for various scenarios. We are committed to providing excellent after - sales service. Our 7*24 - hour customer service team is always online to answer your questions.