12" X 20" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 14 5/8" X 22 5/8"] 18" Round Duct Pipe + Product Details Size –

+ Product Details Size – 18"w X 18"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 22 5/8" width X 12 5/8" height -

+ Product Details Size - 34"w X 32"h is the size for the duct opening measurement only

+ Product Details Size - 8"w X 24"h is the size for the duct opening measurement only

which the interior PET provides

12" X 20" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 14 5/8" X 22 5/8"] 18" Round Duct Pipe + Product Details Size –+ Product Details Size 12"w X 20"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 14 5 8" width X 22 5 8" height Actual Filter Size 11 3 4"w x 19 3 4" x 1" High quality High quality solid stamped steel with counter sunk screw holes (screws included) and no sharp edges Location Sidewall and ceiling Design Removable door face for easy filter change & cleaning uses a 1" thick filter. Our filter