20" x 28" or 28" x 20" Cube Core Eggcrate Return Air Grille w12h12 + Product Details Size -

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

+ Product Details Heavy-Duty Steel Construction - Made from 20-gauge steel for superior durability and reliable performance

+ Product Details Size - 25"w X 30"h is the size for the duct opening measurement only

our grill boasts an impressive 96% airflow capacity

actual front end outer dimensions are 37

20" x 28" or 28" x 20" Cube Core Eggcrate Return Air Grille w12h12 + Product Details Size -+ 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