DESC: Vornado Vortex Action circulates and cleans all the air in the room using 99.97% efficient True HEPA filtration. Verified high-performance output in rooms as large as 14' x 16'. 3-speed control. PreSorb(R) activated carbon prefilter reduces odors and many organic compounds. Thoughtful engineering and design features include a top clean air outlet for effective room air filtration, small footprint and distinctive sculptural shape.