18" x 22" or 22" x 18" Cube Core Eggcrate Return Air Grille flat stamped steel Adjustable airflow control - by

Adjustable airflow control - by rotating the middle disk

Actual Filter Size – 11 3/4"w x 15 3/4" x 1"

actual front end outer dimensions are 26

+ Product Details Size - The listed 8" diameter refers specifically to the size of the duct opening

18" x 22" or 22" x 18" Cube Core Eggcrate Return Air Grille flat stamped steel Adjustable airflow control - by+ Product Details Size 18" x 22" or 22" x 18" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 19. 75" X 23. 75". High Quality High quality, rust free aluminum construction with smooth finished edges and counter sunk screw holes (screws included); no sharp edges.. Installation Location sidewall and ceiling. Design Cubic core eggcrate design Offers highest airflow efficiency at almost 95%, reducing