1. Large LCD screen with different color indicators for varying air quality: 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. 2. Compact size and easy to carry. Ventilation holes on the back accelerate convection between the air and the machine for efficient detection and provide effective heat dissipation. 3. No calibration needed; start testing immediately. Accurately detects carbon dioxide levels for use in greenhouse cultivation, agricultural production, production warehouses, laboratories, homes, etc. 4. The CO2 gas analyzer uses a semiconductor TVOC sensor to calculate carbon dioxide concentration, offering stable performance, low consumption, and long service life. 5. Features a 1200 mAh large-capacity battery for extended working time and a Type-C charging interface for easy charging. 6. We all know that air is an indispensable part of our lives. Air quality affects our body and mind, but air is colorless and tasteless, so we can't measure it with our eyes. At this time, we need an air tester to help monitor air quality. CO2 Measuring Range: 400-5000 ppm Temperature Measuring Range: 0-50 °C Humidity Measuring Range: 0%-99% RH Battery: 3.7V, 1200 mAh Sensor: Semiconductor TVOC Sensor Item Size: 90 x 70 x 35 mm / 3.5 x 2.8 x 1.4 inches Material: ABS Color: White Package Contents: 2 x Air Quality Analyzer 2 x Charging Cable Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.