The BY750 is one of the most advanced and powerful air purification systems available in the market today. This system was certificated by AHAM( The Association of Home Appliance Manufacturer) for one of the highest ratings of CADR in the World. This unit is quiet and efficient and is used for spaces up to 1500-2500 SQ FT. The units is recommended for removing tobacco smoke, odors, pollen grains, house dust mites, mold spore, pet dander, and general indoor air pollutants, and for killing bacteria.