With 14 years experiences in IAQ products design and production, long-term export to Europe and the United States and the Gulf region, many project experiences Built-in commercial-grade high-precision particle sensing module for accurate measurement of parameters and high cost performance ratio. Up to eight parameters are available to meet almost needs for monitoring atmospheric, tunnel, underground and semi-underground environment. Rain & snow-proof, high temperature resistant design with IP53 protection rating. Suitable for air quality monitoring in harsh environments, available for data from the nearest outdoor environment Provide a variety of communication interface options, connect monitoring and analysis software platform for data storage, analysis and comparison Working with indoor air quality monitors together, as the comparison and analysis of indoor and outdoor data, and develop air quality improvement or energy saving solutions.