All F111 Series devices may use the Honeywell 95% ASHRAE Replacement Media Filter, which was created with that purpose in mind. These filters maintain Honeywell's tradition of producing products and accessories that deliver elite performance at a fraction of the cost. These Certified Honeywell Filters have a MERV 14 Rating and have been shown to be 90-95% effective in removing harmful particles like dust, pollen, and grime. Additionally, Certified Honeywell Filters provide great output with less resistance. With a Certified Honeywell Filter, obtain the highest level of peace of mind and reject imitations. Dimensions: 22-1/4 x 22-1/4 x 3-5/8 in.