Feature: 1. Large Screen: The carbon dioxide detector is equipped with a large screen. Different font colors show different air quality. Green flashes at 0‑999ppm, and yellow flashes at 1000‑1999ppm, orange flashes at 2000‑2900ppm, red flashes at 3000‑3999ppm, and the above 4 colors flash at 4000ppm. 2. Accurate Measurement: This air quality monitor adopts a special premium electrochemical detection module, which has good accuracy, stable performance, strong anti interference ability and low consumption. 3. Ventilation Hole Design: The left and right hundreds of ventilation holes not only accelerate the convection between the air and the machine, so as to achieve effective detection, but also provide good heat dissipation effect. 4. Easy to Use: The carbon dioxide tester does not need calibration, and can be used to test the air quality when starting up, the can well detect the carbon dioxide. 5. Long Service Life: This infrared carbon dioxide detector is made of premium ABS material, which is compact and not easily be damaged, and can be used for a long time. Specification: Item Type: Carbon dioxide detector Material: ABS Weight: Approx. 227g/8z Color: Black Product Size: 14x8x3.7cm/5.5x3.1x1.4in Voltage: 5V Current: 1A Carbon Dioxide Detection Range: 400-5000ppm Carbon Dioxide Detection Accuracy: 1ppm Temperature Measurement Range: 1-70℃ Temperature Measurement Accuracy: ±0.2℃(0-65 ° C) Humidity Measurement Range: 0% - 99%RH Humidity Measurement Accuracy: ±2%RH Battery: 18650 polymer lithium battery or 3 AA batteries(Shipped without battery). Package List: 1 x Host1 x USB Line1 x Instructions