20" x 28" or 28" x 20" Cube Core Eggcrate Return Air Grille 10in diameter Actual Filter Size – 19

Actual Filter Size – 19 3/4"w x 25 3/4" x 1"

+ Product Details Size - 3" Diameter is the size for the duct opening measurement only

+ Product Details Size – 14"w X 28"h is the size for the duct opening measurement only

+ Product Details Size - 18"w X 10"h is the size for the duct opening measurement only

it's built to last and will never rust

20" x 28" or 28" x 20" Cube Core Eggcrate Return Air Grille 10in diameter Actual Filter Size – 19+ Product Details Size 20" x 28" or 28" x 20" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 21. 75" X 29. 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