20" X 20" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 22 5/8" X 22 5/8"] Material_Aluminum With a 6" diameter for

With a 6" diameter for the duct opening measurement

+ Product Details Size – 18"w X 18"h is the size for the duct opening measurement only

with actual outer dimensions of 14

High Quality – Solid rigid steel body for durability and reliability

actual front end outer dimensions are approximately 18 5/8" width X 16 5/8" height

20" X 20" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 22 5/8" X 22 5/8"] Material_Aluminum With a 6" diameter for+ Product Details Size 20"w X 20"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 22 5 8" width X 22 5 8" height Actual Filter Size 19 3 4"w x 19 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.