Improves air quality by continuously removing and effectively reducing over 350 moderate to heavy levels of gases and odors from a variety of sources. All this without creating harmful ozone. Carbon filter contains activated carbon media treated for removal of formaldehyde. Charcoal weight 6350 grams, RoHS compliant. 3 air speeds with 8 air changes/hour on high; 4 changes/hour on medium; 2 changes/hour on low (measured in a 5000 cu ft room). Limited warranty can be extended with the replacement of the carbon filter every 12 months.