28" X 10" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 30 5/8" X 12 5/8"] Powder-Coat + Product Details Size - RG1620AL Quality Packaging carefully packaged 8 Feet Long

+ Product Details Size - 26"w X 16"h is the size for the duct opening measurement only

+ Product Details Size - 20"w X 16"h is the size for the duct opening measurement only

& EN 13180 standards

actual front end outer dimensions are approximately 20 5/8" width X 28 5/8" height

28" X 10" Steel Return Air Filter Grille for 1" Filter Removable Frame [Outer Dimensions: 30 5 8" X 12 5 8"] Powder Coat + Product Details Size RG1620AL Quality Packaging carefully packaged 8 Feet Long + Product Details Size 26"w X 16"h is the size for the duct opening measurement only + Product Details Size 20"w X 16"h is the size for the duct opening measurement only