Maintain high efficiency levels of your HVAC equipment. Help protect your family and home from airborne particulates, allergens, dust, and dander. Incredible standard MERV 11 filtration rate. Cleans the air in your entire home every time your heating or cooling system is on. Easy filter cartridge replacement lasts up to 12 months*. To complete and optimize your indoor air quality, consider adding the TopTech Whole House UV Air Treatment System. Air Handler Sizes: #TT-MAC-1722: (22.125 D x 17 This filter replaces the following filters: TT-MAC-2122