12" X 24" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 14 5/8" X 26 5/8"] w10h10 + Product Details Size –

+ Product Details Size – 12"w X 18"h is the size for the duct opening measurement only

With a 4" diameter for the duct opening measurement

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

875" width X 21

12" X 24" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 14 5/8" X 26 5/8"] w10h10 + Product Details Size –+ Product Details Size 12"w X 24"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 14 5 8" width X 26 5 8" height Actual Filter Size 11 3 4"w x 23 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