20" X 26" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 22 5/8" X 28 5/8"] w12h12 but still very thin

but still very thin

actual front end outer dimensions are approximately 10 5/8" width X 14 5/8" height

Great emphasis has been invested in the design of this product to prevent it from kinking in sharp bends & turns and to hold steady and at full diameter in all applications

+ Product Details Size – 4"w X 10"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 20 5/8" width X 22 5/8" height

20" X 26" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 22 5/8" X 28 5/8"] w12h12 but still very thin+ Product Details Size 20"w X 26"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 22 5 8" width X 28 5 8" height Actual Filter Size 19 3 4"w x 25 3 4" x 1" High Quality High quality solid stamped steel with counter sunk screw holes (screws included) and no sharp edges Installation Location Sidewall and ceiling Design Removable door face for easy filter change & cleaning uses a 1" thick filter.