Most can-type air filters utilize 50% of the carbon available by only filtering through the top section of the carbon filter, leaving the bottom section unused. PROfilters use an innovative patented design allowing the user to reverse the filter, benefiting from the use of 100% of the carbon available and effectively increasing the units’ lifespan. Manufactured with only the finest TC940 virgin 3mm grain sized carbon. PROfilters effectively remove 99.5% of odors. It is rated for a continuous worry-free operation and available in seven different sizes and CFM ratings, PROfilters are recommended for commercial or residential use. Flange not included.