30" X 18" Steel Return Air Filter Grille for 1" Filter - Removable Frame - Black - [Outer Dimensions: 32 5/8" X 20 5/8"] Adjustable Return + Product Details Size -

+ Product Details Size - 8"w X 28"h is the size for the duct opening measurement only

Both lines taped together every 18in for easier handling & installation

+ Product Description Enhance your ventilation system with our high-quality grilles and registers

and the second number represents the height

30" X 18" Steel Return Air Filter Grille for 1" Filter - Removable Frame - Black - [Outer Dimensions: 32 5/8" X 20 5/8"] Adjustable Return + Product Details Size -+ Product Details Size 30"w X 18"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 32 5 8" width X 20 5 8" height Actual Filter Size 29 3 4"w x 17 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.