25" X 34" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 27 5/8" X 36 5/8"] sidewall + Product Details Size -

+ Product Details Size - The listed 4" diameter refers specifically to the size of the duct opening

+ Product Details Size – 20"w X 16"h is the size for the duct opening measurement only

+ Product Details Size - 10"w X 14"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 30 5/8" width X 12 5/8" height

+ Product Details Size - 6"w X 6"h is the size for the duct opening measurement only

25" X 34" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 27 5/8" X 36 5/8"] sidewall + Product Details Size -+ Product Details Size 25"w X 34"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 27 5 8" width X 36 5 8" height Actual Filter Size 24 3 4"w x 33 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.