Unpleasant odors are no match for the Freshmaker! This charcoal fiber air filter is capable of removing foul-smelling particles from the air in one pass, even at high flow rates. The Freshmaker's unique design and high-quality active carbon allow it to be both compact and highly effective whether used for intake or exhaust on the front or back end of a ventilation system. This 4" filter is rated for up to 516cfm.  The filter has a 4" Flange, 6" Diameter, 7.25" Height.