Nano Cold Catalyst filter : Eliminating cigarette smoke and all sorts of offensive odors, leave indoor air fresh and clean. Decomposing the harmful gas and substances in the air (formaldehyde, ammonia, benzene). Helping the metabolism of the human body by generating the anions by cracking harmful molecules. High performance in gaseous particle removal, reliable quality.Adsorb wide variety of harmful chemicals, eliminates smells and VOC. Activated Carbon Filter : Activated carbon is a porous material that adsorbs volatile chemicals on a molecular basis. The adsorption process when using activated carbon must reach equilibrium thus it may be difficult to completely remove contaminants. Activated carbon is merely a process of changing contaminants from a gaseous phase to a solid phase, when aggravated or disturbed contaminants can be regenerated in indoor air sources. Activated carbon can be used at room temperature and has a long history of commercial use. It is normally used in conjunction with other filter technology, especially with HEPA. Other materials can also absorb chemicals, but at higher cost. Absorb formaldehyde, a compound found in carpet, wood paneling, and furniture upholstery. Perfumes and chemicals in household cleaning items are also removed, making the environment much more breathable for all, especially asthma sufferers, babies, children, and the elderly.