TVOC: 0-9.999mg/m³. HCHO detection range: 0-9.999mg/m³. 1 Air Detector. CO2 detection range: 400-5000PPM. ★ Four-color alarm: There are four different colors to show the different quality of the air being monitored: green for good air quality, and colors from yellow to orange to red for poor air quality.
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