16" X 16" Steel Return Air Filter Grille for 1" Filter - Removable Frame - * Filter Included * [Outer Dimensions: 18 5/8" X 18 5/8"] 18" Round Duct Pipe actual front end outer dimensions

actual front end outer dimensions are approximately 32 5/8" width X 14 5/8" height

Actual Filter Size – 31 3/4"w x 11 3/4" x 1"

+ Product Details Size - 16"w X 18"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 27 5/8" width X 26 5/8" height

+ Product Details Size – 30"w X 34"h is the size for the duct opening measurement only

16" X 16" Steel Return Air Filter Grille for 1" Filter - Removable Frame - * Filter Included * [Outer Dimensions: 18 5/8" X 18 5/8"] 18" Round Duct Pipe actual front end outer dimensions+ Product Details Size 16"w X 16"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 18 5 8" width X 18 5 8" height Actual Filter Size 15 3 4"w x 15 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.