The Sharp KC860U Air Purifier and Humidifier has many layers to it.
The triple filtration system helps clean the air that passes through the filters in three ways. The washable, microscreen pre-filter traps dust and other large airborne particles. The activated carbon deodorizing filter helps reduce some common household odors. Finally, the True HEPA filter effectively captures 99.97% of particles from the air that passes through the filter from 0.3 microns and larger