The Pinotec AK3 Indoor Hygrometer is a versatile 5-in-1 device that functions as a gas detector and air quality monitor. With a digital display, it measures PM2.5 levels, C02, HCHO, TVOC, and AQI, providing comprehensive information on indoor air quality. Designed for indoor use, this device is a valuable tool for monitoring and maintaining a healthy environment. Made in China, this standalone unit offers convenience and accuracy in assessing various air quality parameters.