34" X 34" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 36 5/8" X 36 5/8"] 2-Way + Product Details Size –

+ Product Details Size – 10" x 20" or 20" x 10" is the size for the duct opening measurement only

+ Product Details Size - 28"w X 22"h is the size for the duct opening measurement only

Rigid gauge built for durability and long life in mind

and its seamless drop-in installation process ensures effortless setup

34" X 34" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 36 5/8" X 36 5/8"] 2-Way + Product Details Size –+ Product Details Size 34"w X 34"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 36 5 8" width X 36 5 8" height Actual Filter Size 33 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.