Sharper Image SI867 Ionic Breeze Air Purifier Filter Sharper Image air purifier is an electrostatic air cleaning system Air purifier ideal for larger rooms, more polluted environments or highly-sensitive individuals Ozone guard with PremAir catalyst from BASF Catalysts LLC coverts by-product ozone to oxygen. Three charged collector blades have two inert diverter blades in between to significantly improve their particle capture rate electronic propulsion air purifier circulates air with no motor Air purifier's energy use is no more than 10 watts to operate 24 hours a day 7 days a week