The air purifier by 3M effectively removes dust, dander, mold, smog, and smoke from indoor environments. The attractive, room-size device measures 21 inches x 16 inches x 6.75 inches and offers around-the-clock protection. The convenient, push-button controls allow you to turn the unit on and off, set the timer, and adjust the level of air filtration. Maintenance is a snap. Simply remove the front grill and replace the filter for continued, optimal air quality.