1) CADR:120cfm(Smoke), Energy star compliant. 2) Five-speed fan to meet both quiet and powerful performance. 3) Replacement TRUE HEPA filter (99.97% filtration down to 0.3 microns). 4) Active carbon Pre-filter removes smell and big particles. 5) TiO2 coated on UVC lamp shield helps to removes odor. 6) UVC(5W) germicidal lamp ensures bacteria free. 7) Negative ionizer( if need, 1.5USD added ): 3 million icons/cubic meter. 8) Suitable for room at least 18 sqm, 5 times recycle in one hour 9) Less than 60dB(Ambient noise 35dB)