20" X 30" Steel Return Air Filter Grille for 1" Filter - Removable Frame - Black - [Outer Dimensions: 22 5/8" X 32 5/8"] Color_R-4.2 Yellow + Product Details Size - 75 Width X 17 LO3634 w20h20

+ Product Details Size - 22"w X 28"h is the size for the duct opening measurement only

+ Product Details Size - 26"w X 26"h is the size for the duct opening measurement only

+ Product Details Size – 26"w X 16"h is the size for the duct opening measurement only

+ Product Details Size - The listed 8" diameter refers specifically to the size of the duct opening

so you are not left with much waste

20" X 30" Steel Return Air Filter Grille for 1" Filter Removable Frame Black [Outer Dimensions: 22 5 8" X 32 5 8"] Color_R 4.2 Yellow + Product Details Size 75 Width X 17 LO3634 w20h20 + Product Details Size 22"w X 28"h is the size for the duct opening measurement only + Product Details Size 26"w X 26"h is the size for the duct opening measurement only