Actual Dimensions: 15.5 x 19.88 x 4.25. Accumulair brand 16x20x4.5 Carrier FAIC0017A02 style whole house filters, exactly engineered to substitute for the name brand Carrier FAIC0017A02 filters. Fully assembled so no assembly or combs required. MERV classified to ASHRAE 52.2 test specifications ensuring particulate filtration as good or better than the name brand Carrier FAIC0017A02 air filter. Notice: Sample air filter image shown is not the actual dimensions and is there to show design purposes. Name brands and Carrier FAIC0017A02 P/N are listed for air filter replacement identification use.