8" X 12" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 10 5/8" X 14 5/8"] Material_Steel provides a modern look and 4 X 12 Is CRFG2028 Width_14in

provides a modern look and quiet operation due to its half-inch by half-inch cube design

+ Product Details Size - 24"w X 4"h is the size for the duct opening measurement only

+ Product Details Size – 12"w X 8"h is the size for the duct opening measurement only

Insulation – A thick blanket of fiberglass insulation provides you with an R-Value of 4

+ Product Details Size - 30"w X 28"h is the size for the duct opening measurement only

8" X 12" Steel Return Air Filter Grille for 1" Filter Removable Frame [Outer Dimensions: 10 5 8" X 14 5 8"] Material_Steel provides a modern look and 4 X 12 Is CRFG2028 Width_14in provides a modern look and quiet operation due to its half inch by half inch cube design + Product Details Size 24"w X 4"h is the size for the duct opening measurement only