6" x 20" or 20" x 6" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 8.5" X 22.5"] 12in diameter + Product Details Size – Suitable for all AC 8in diameter 12125SDCLNGBX

+ Product Details Size – 14" x 30" or 30" x 14" is the size for the duct opening measurement only

+ Product Details Size – 20"w X 25"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 26" x 20" OR 20" x 26" duct opening (measured at the opening)

+ Product Details Size - 8"w X 22"h is the size for the duct opening measurement only

6" x 20" or 20" x 6" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Aluminum White [Outer Dimensions: 8.5" X 22.5"] 12in diameter + Product Details Size – Suitable for all AC 8in diameter 12125SDCLNGBX + Product Details Size – 14" x 30" or 30" x 14" is the size for the duct opening measurement only + Product Details Size – 20"w X 25"h is the size for the duct opening measurement only