Large LCD screen displays air quality with different font colors: green for 400-799ppm, yellow for 800-1199ppm, orange for 1200-1599ppm, red for 1600-1999ppm, and all four colors flash when CO2 levels exceed 2000ppm. Compact and portable design with rear ventilation holes that enhance air convection for effective detection and provide efficient heat dissipation. No calibration required; ready to use upon startup. Accurately detects carbon dioxide levels and is suitable for use in greenhouses, agricultural production, warehouses, laboratories, homes, and more. Uses a semiconductor TVOC sensor to estimate carbon dioxide concentration, offering stable performance, low power consumption, and long service life. Equipped with a 1200mAh rechargeable battery for extended operation and features a Type-C charging port for convenient charging. Color: Black Material: Plastic Size: 90 x 35 x 70mm Package Contents: 1 x Air Quality Monitor 1 x Charging Cable 1 x English Manual Note: The package includes only the items listed above. Other items are not included. Note: Lighting and display settings may cause slight variations in the color shown in the image compared to the actual product. Measurement error is +/- 1-3cm.