HQRP 4-Pack Carbon Pre-Filter C fits Holmes HAPF600, HAPF600D, HAPF600D-U2, HAPF600PDQ, HAPF600CS HEPA Air Cleaner Filters Coaster HQRP&reg; 4pcs Carbon Odor Air Purifiers Filter C plus HQRP&reg; Coaster; Enhanced with baking soda to absorb and eliminate household odors; Traps household chemicals and cigarette smoke; For use with See Side Panel, cannot be used independent of the main purifier filter; Dimension size: 6 x 9.25 inches; 2 weeks DOA replacement warranty!