Dyson AM11 Pure Cool Tower Purifier Fan | Refurbished The Dyson AM11 Pure Cool purifier fan is wrapped with a 360 degree, vacuum-sealed glass HEPA filter that removes 99.97% of allergens and pollutants as small as 0.3 microns from your home including pollen, bacteria and pet dander. A layer of activated carbon granules captures odors and harmful toxins like paint fumes. Purification all year round. Purifying fan in summer. Year-round purification and circulation. Smooth, long-range air flow to cool you in summer. LED display Dims - no disturbance. Easy filter change - instead of washing a filter every month, just replace it after a year of using it for 12 hours every day.