Whirlpool 1183900 HEPA Filter Tower Air Purifier, Design to Fit Air Purifier Model APT30010M, APT40010R, APT42010M, APT50010M and APMT2001M, 10.1x4.6 inch For WhirlPool Models: APT30010M, APT40010R, APT42010M, APT50010M and APMT2001M New True HEPA Replacement Filter (Tower and Portable Tower). Requires (2) filters for Tower Air Purifiers and (1) filter for Portable Tower Air Purifier Improves and maintain clean fresh air quality in the house. Removes and eliminates airborne particles or indoor air pollutants such as household dust, pet dander, Tobacco smoke, mold spores, plant pollen and fabric fibers. Filter reduces 99.97% airborne particles as small as 0.3 microns.