Features: Large LCD screen; different color indicators display varying air quality levels: green (400-799 ppm), yellow (800-1199 ppm), orange (1200-1599 ppm), red (1600-1999 ppm), and all four colors flashing simultaneously above 2000 ppm. Compact and portable design. Rear ventilation holes enhance air circulation for efficient detection and provide effective heat dissipation. No calibration needed; ready-to-use upon startup. Provides accurate CO2 detection, ideal for greenhouses, agricultural production, warehouses, laboratories, homes, and more. Versatile and practical; useful for epidemic prevention and control by monitoring CO2 concentration in populated areas to manage crowd size and reduce cross-infection risks. High-capacity 1200 mAh battery for extended use; features a convenient Type-C charging port. Specifications: Color: White CO2 Measurement Range: 400-5000 ppm Temperature Measurement Range: 0-50°C Humidity Measurement Range: 0-99%RH Battery: 3.7V, 1200 mAh Product Dimensions: 90 x 70 x 35 mm / 3.5 x 2.8 x 1.4 inches Product Weight: 117 g / 4.1 oz Package Dimensions: 140 x 125 x 41 mm / 5.5 x 4.9 x 1.6 inches Package Weight: 173 g / 6.1 oz Package Contents: 1 x Air Quality Analyzer 1 x USB Cable 1 x User Manual