14" X 16" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 16 5/8" X 18 5/8"] w10h10 + Product Details Size – 4 X 12 Is CRFG2028 Width_14in

+ Product Details Size – 20"w X 30"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 26 5/8" width X 38 5/8" height -

actual front end outer dimensions are approximately 34 5/8" width X 20 5/8" height

Pre-flared ends with nuts are for simple and easy installation

+ Product Details Size – 18"w X 12"h is the size for the duct opening measurement only

14" X 16" Steel Return Air Filter Grille for 1" Filter Removable Frame [Outer Dimensions: 16 5 8" X 18 5 8"] w10h10 + Product Details Size – 4 X 12 Is CRFG2028 Width_14in + Product Details Size – 20"w X 30"h is the size for the duct opening measurement only actual front end outer dimensions are approximately 26 5 8" width X 38 5 8" height