36" X 18" Steel Return Air Filter Grille for 1" Filter - Fixed Hinged - [Outer Dimensions: 38 5/8" X 20 5/8"] ceiling + Product Details Size -

+ Product Details Size - 28"w X 26"h is the size for the duct opening measurement only

+ Product Details Size - 12"w X 28"h is the size for the duct opening measurement only

5" - SEE BELOW IN DESCRIPTION How To Measure A Grille

+ Product Details Size - 12"w X 24"h is the size for the duct opening measurement only

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

36" X 18" Steel Return Air Filter Grille for 1" Filter - Fixed Hinged - [Outer Dimensions: 38 5/8" X 20 5/8"] ceiling + Product Details Size -+ Product Details Size 36"w X 18"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 38 5 8" width X 20 5 8" height High Quality High quality solid stamped steel with counter sunk screw holes (screws included) and no sharp edges Installation Location Ceiling Design Fixed hinged for easy filter change & cleaning uses a 1" thick filter. Our filter grille latch is easy to use on your fingers and