DESC: Winix 5-stage air cleaning system includes a washable and anti-bacterial pre-filter, True HEPA filter with 99.99% efficiency, Nano-Silver mesh, washable carbon filter and the PlasmaWave™ Technology.Winix PlasmaWave™ creates Hydroxyls which attack dangerous airborne pollutants such as viruses, bacteria and chemical vapors (VOCs), as well as common household odors caused by pets, tobacco smoke and cooking.