10" x 20" or 20" x 10" Cube Core Eggcrate Return Air Grille 18" Round Duct Pipe + Product Details Size -

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

DIY projects

+ Product Details Size - 30"w X 14"h is the size for the duct opening measurement only

+ Product Details Size – 24"w X 24"h is the size for the duct opening measurement only

Its smooth

10" x 20" or 20" x 10" Cube Core Eggcrate Return Air Grille 18" Round Duct Pipe + Product Details Size -+ Product Details Size 10" x 20" or 20" x 10" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 11. 75" X 21. 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