12" x 20" or 20" x 12" Cube Core Eggcrate Return Air Grille Brown + Product Details Size –

+ Product Details Size – 36"w X 22"h is the size for the duct opening measurement only

5/8" - 2579 PSI

featuring a 8" round duct opening

actual front end outer dimensions are 5" diameter

+ Product Details Size – 8" x 12" or 12" x 8" is the size for the duct opening measurement only

12" x 20" or 20" x 12" Cube Core Eggcrate Return Air Grille Brown + Product Details Size –+ Product Details Size 12" x 20" or 20" x 12" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 13. 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