14" X 28" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 16 5/8" X 30 5/8"] Adjustable Return + Product Details Size - 6in diameter LO3236 Easily adjust dimensions with

+ Product Details Size - 36"w X 6"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 12 5/8" width X 26 5/8" height

actual front end outer dimensions are approximately 7

+ Product Details Size – 8"w X 20"h is the size for the duct opening measurement only

14" X 28" Steel Return Air Filter Grille for 1" Filter Removable Frame [Outer Dimensions: 16 5 8" X 30 5 8"] Adjustable Return + Product Details Size 6in diameter LO3236 Easily adjust dimensions with + Product Details Size 36"w X 6"h is the size for the duct opening measurement only actual front end outer dimensions are approximately 12 5 8" width X 26 5 8" height