18" X 10" Steel Return Air Filter Grille for 1" Filter - Fixed Hinged - [Outer Dimensions: 20 5/8" X 12 5/8"] w8h8 you can attain the diameter

you can attain the diameter of the vent

no questions asked

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

We carry sizes the big box stores don't

+ Product Details Size - 34"w X 20"h is the size for the duct opening measurement only

18" X 10" Steel Return Air Filter Grille for 1" Filter - Fixed Hinged - [Outer Dimensions: 20 5/8" X 12 5/8"] w8h8 you can attain the diameter+ 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