iPower 4 Inch Air Carbon Filter Odor Control Scrubber with Australia Virgin Charcoal for Inline Fan, Reversible Flange, Prefilter Included Air Flow: 200CFM; Dimensions: 4" Flange Ducting x 12" Length 1050+ IAV Australian RC412 Activated Carbon: One of the world's most absorbent carbon available Extended Service Life: Reversible flange and base intended for extended service life, up to 2 years in life expectancy Pre-Filter included: We recommend replace the Pre-Filter every 6 months to protect your filter Effective Odor Control: The filter will soak up and eliminate some of the most undesirable odors and additional harmful and potentially ill-fating chemicals in the air. 50mm Carbon Layer of Thickness for Higher Absorption and Performance. 1050+ IAV Australian RC412 Activated Carbon: One of the world&#039;s most absorbent carbon available. Reversible flange and base intended for extended service life. Pre-Filter included: We recommend replace the Pre-Filter every 6 months to protect your filter. Inner and outer mesh with 53% open area allows for increased air flow.