Actual size is 20 x 21.13 x .75. Accumulair brand 21x21.5x1 American Standard TFP210A0FR10 compatible whole house filters, specifically constructed to replace the name brand American Standard TFP210A0FR10 air filters. Completely built - no forming or combs required. MERV rated to ASHRAE 52.2 test standards establishing particle capture to the level of the name brand American Standard TFP210A0FR10 air filters. Note: Example filter image as shown is not to scale and is there to show construction only. Trade names and American Standard TFP210A0FR10 P/N displayed for filter style identification use.