Sharp IGA10AUW Ultra High Density Plasmacluster Ion Generator Recommended for spaces up to 108 sq. ft. Long Life Ion Engine allows for up to 2 years of continuous use or a total of up to 19,000 hours 2 washable micro-filters traps dust, dirt and other airborne particles Library Quiet noise level is 34 dB on low (44 dB on high) Energy efficient operation uses only 5.8 watts on low and 14 watts on high