26" x 30" or 30" x 26" Cube Core Eggcrate Return Air Grille 6" Diameter + Product Details Size – 4 X 12 Is CRFG2028 Width_14in

+ Product Details Size – 20" x 32" or 32" x 20" is the size for the duct opening measurement only

actual front end outer dimensions are approximately 42 5/8" width X 22 5/8" height -

+ Product Details Perfect Fit & Easy Sizing - Designed for a 26" x 18" OR 18" x 26" duct opening (measured at the opening)

Actual Filter Size – 11 3/4"w x 25 3/4" x 1"

+ Product Details Size – 14" x 22" or 22" x 14" is the size for the duct opening measurement only

26" x 30" or 30" x 26" Cube Core Eggcrate Return Air Grille 6" Diameter + Product Details Size – 4 X 12 Is CRFG2028 Width_14in + Product Details Size – 20" x 32" or 32" x 20" is the size for the duct opening measurement only actual front end outer dimensions are approximately 42 5 8" width X 22 5 8" height