Product Detail Circulates air-cleaning negative ions. Found by the U.S. Dept. of Agriculture to be 99% effective against airborne dust & particles.(Covers 500 SQ FT) Proven Performance - Nearly 100% Effective in Clinical Particle Removal Tests. No Replacement Costs. Just wipe off the metal collector grid. Saves you hundreds in replacement filters over the life of the unit. The built-in, independently-controlled fan effectively moves the air, increasing air-cleaning efficiency.( AS SEEN ON TV ) Costs Just Pennies a Day to Operate. Uses less electricity than a light bulb, saving you hundreds more over the life of the unit, compared to most air purifiers . The "The HF-2100 UV Air Purifier" is best product for you. We recommended The HF-2100 UV Air Purifier