We all know that air is an indispensable part of our lives. Air quality ma effects on our body and mind, ale air is colorless and tasteless, we cannot measure it with our eyes. Right now, we need an air tester to help monitor air quality. Color liquid crystal display (LCD) with a diagonal of 2,8 inches, 320 * 240 pixels. User-adjustable alarm threshold for O3 to alert the user of elevated level. Can be used in offices, outdoors and do detect ozone residues after disinfection. Large lithium battery with a capacity of 2000 mAh. Built-in fan do suck air from the environment for more accurate results in real time. Specifications: Material: ABS Kolor: black orange Screen Size: 2,8 inch Concentration O3 AQI: 00,100: Good 0,1000,300: Light 0,3001,000: Moderate 1,0004,999: Serious Battery: 1 * Lithium battery, 2000 mAh (included) Item Size: 164 * 74 * 26 mm / 6,5 * 2,9 * 1,0 inch Package Weight: 501 g / 1,1 lb Packing list: 1 * Air Quality Detector 1 * USB cable 1 * User Manual 1 * Box