This product is a simple and reliable measuring instrument that combines ease of use and performance, it allows you to track 4 for key air quality factors: TVOC, HCHO, Formaldehyde pollution index, AQI. Features: This product adopts environmentally-friendly material, bracket design which is more comfortable to use. Conveniently placed in every corner of the home, truly real-time comprehensive detection of air quality problems. High accuracy, use air analysis technology to accurately locate tiny harmful components in the air to ensure sensitivity to substances such as formaldehyde. Avoids the cumbersome data when using, adopt the pollution level division mechanism, the level is clear and easy to read and take anti-pollution measures earlier. Lithium battery is selected to ensure long-term standby for time and long-term monitoring for time without any omission. Orderly, at a glance, four levels of classification, throwing away cumbersome data reading, making the review easier. Specifications: Screen size: 2.8in Detection error: less than 15% Sampling speed: less than 3 seconds Range: 0-2.888mg/m3(formaldehyde), 0.000-9.999mg/m3(TVOC) Battery: 2.5-3.2V, 2200mAh Standby time: about 12 hours Detection range: formaldehyde, TVOC, carbon dioxide, PM2.5, PM10 detection average recording function Item size: 15x6.8cm(5.9x2.67Inch) Quantity: 1Pc Note: And due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! Package list: 1 * Air Quality Tester 1 * USB Cable 1 * User Manual