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

+ Product Details Size – 22"w X 25"h is the size for the duct opening measurement only

And is classified as Class 1 Fire Proof - B1

4" X 10" Is The Size For The Duct Opening (floor/vent hole) Measurement Only

Actual Filter Size – 9 3/4"w x 27 3/4" x 1"

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