18" X 10" Steel Return Air Filter Grille for 1" Filter - Fixed Hinged - [Outer Dimensions: 20 5/8" X 12 5/8"] w8h8 + Product Details Size –

+ Product Details Size – 12"w X 36"h is the size for the duct opening measurement only

+ Product Details Size - 8"w X 14"h is the size for the duct opening measurement only

you can attain the diameter of the vent

We carry sizes the big box stores don't

actual front end outer dimensions are approximately 16 5/8" width X 12 5/8" height

18" X 10" Steel Return Air Filter Grille for 1" Filter - Fixed Hinged - [Outer Dimensions: 20 5/8" X 12 5/8"] w8h8 + Product Details Size –+ Product Details Size 18"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 12 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