Actual dimensions are 19.75 x 19.88 x 4.38. Brand: Accumulair. 20x20x5 Honeywell FC100A1011 replacement whole house air filters, specifically built to be an alternative to the name brand Honeywell FC100A1011 filters. Completely built - no assembly or combs needed. MERV graded to ASHRAE 52.2 test standards ensuring performance to the level of the original brand Honeywell FC100A1011 filter. Notice: The sample filter image shown is not the actual dimensions and is shown for configuration purposes. Name brands and Honeywell FC100A1011 P/N included for air filter substitution identification.