Blueair Pro AIM, Air Intelligence Module, Air Quality Sensor Compatible with Blueair Pro M, Pro L and Pro XL Air Purifiers Air Quality sensor - aim, allows the Pro air cleaning systems to display the air Quality in a simple and easy to read format through an LED light on top of the units Auto mode -the aim allows for the Pro units to select the proper fan speed to eliminate particles, allergens, pollen, dust, VOCs, odors and smoke The air intelligence module is standard with the Pro XL, and is compatible with the Blueair Pro M and Blueair Pro L air cleaners Professional performance for doctors office, work spaces, meeting rooms, labs, lobby, or in the house