Smile Bud Hydroponic Air Carbon Filter and Odor Control Scrubber For Growing Tent (4-Inch by 10-Inch) High CFM Air Flow Carbon Fliter 4 Inches Compatible Connection Flange With Washable PRE-FILTERS To Extend The Life Of Carbon Filter And Get Better Control Over Airflow 50mm Carbon Layer of Thickness TO Filter dust particles And Purifying Air Removes 99.8% Of Air Particulates By Activated Charcoal