This is the air purifier with the same industrial HEPA filter used in hospitals. It has a double filtration system that includes a 1" deep carbon/potassium pre-filter that removes odors including tobacco smoke, and a 2 1/2" deep true HEPA filter that traps 99.97% of particles larger than 0.3 microns including pollen, mold, and pet dander. It has five fan speeds that quietly draw air in and creates a healthier environment for people with allergies, asthma, and other respiratory conditions. It filters a 1,500' sq. room two times every hour. Includes one HEPA filter and one carbon filter that each last 12 months. Plugs into AC. 17" W x 10" W x 19" H. (27 lbs.)