Awair Rev2 Air Quality Monitor Tests your air for temperature, humidity, CO2, Particulate Matter down to 2.5 and Volatile Organic compounds (VOCs) This can report data to you via the Awair app and keep a history of your air quality via wifi or it can be used without the app and will show the current readings on the monitor itself. Comes with electrical plug and must be plugged in to work. Plug is usb as well. Works great with minimal cleaning!