Seal Cover for Any 1” Furnace Filter, Up To 25” Long

Video Guide to Filter Lock Furnace Filter Slot Covers and air filter slot cover cover for the filter slot I would think that you would want this covered to help pull air from throughout the air 138 slot Return Air Side of the Air Handler Unit: In these systems, the filter is placed in the designated slot directly attached to the HVAC air handling unit

airport slot coordination A particulate air filter is a device composed of fibrous, or porous materials which removes particulates such as smoke, dust, pollen, mold,