TruSens Carbon Layer Replacement for Z2000AP, 3Pk, 8.5", x 4.7" x 2.6" Depth (TNSAFCZ200001) EachThe DuPont Replacement Carbon features an activated carbon layer to effectively remove certain gases and odors from the air. Filter replacement is essential for your air purifier to perform at its best. For best results, replace the carbon layer filter every three months. Replacement carbon is compatible with all TruSens Medium Air Purifiers (sold separately). General Information Manufacturer: ACCO Brands Corporation Manufacturer Part Number: