The Dyson Pure Cool Link purifier fan automatically removes 99.97 percent of allergens and pollutants as small as 0.3 microns such as pollen, bacteria and pet dander from your home. The 360 degree, vacuum-sealed glass HEPA filter removes indoor air pollutants while a second layer of activated carbon captures household odors and potentially harmful toxins such as paint fumes. Purifies all year round cools you as a fan in summer. Intelligent purification automatically monitors, reacts and purifies - then reports the air quality data to your Dyson link app, so you can remotely control your environment– standard data and messaging rates may apply.. The night-time mode monitors, reacts and purifies, but only using the quiet settings and the LED display dims – for no disturbance for light sleepers. Easy filter change - rather than washing a filter every month, just replace it after a year of using it for 12 hours every day with Dyson Pure Cool Link replacement filters.