HEPAtech 57 Air Purification System 200 CFM multi-stage filtration system cleans air faster than other systems. Removes 99.9% of particles as small as .1 microns. Changes the air 6 times per hour in rooms up to 12 X 12'. Whisper-quiet, 3-speed fan. HEPAtech filter pack maintains air cleaning performance; charcoal filter freshens air. Easy-change, drop-in filter pack with change indicator chart. Attractive styling fits any decor. Five-year warranty on motor; 1-year warranty on parts and labor.