HQRP Filter for Hamilton Beach 04712 True Air Allergen Reducing Filter Replacement plus Coaster HQRP&reg; Replacement Filter plus HQRP&reg; Coaster; Replacement filter for 210 square foot room; For optimum performance, replace the filter every 2 - 3 months; The maximum durability is 120 days; Effective at capturing dust / dust mite debris, mold spores, pollen, smoke and pet dander; Compatible with Original filter. 2 weeks DOA replacement warranty!