16" x 30" or 30" x 16" Cube Core Eggcrate Return Air Grille 8in diameter + Product Details Perfect Fit

+ Product Details Perfect Fit & Easy Sizing - Designed for a 16" x 20" OR 20" X 16" duct opening (measured at the opening)

+ Product Details Size - 40"w X 20"h is the size for the duct opening measurement only

+ Product Details

+ Product Details Size – 26" x 34" or 34" x 26" is the size for the duct opening measurement only

+ Product Description Upgrade your HVAC system with our 6" Round Air Vent Supply Grille

16" x 30" or 30" x 16" Cube Core Eggcrate Return Air Grille 8in diameter + Product Details Perfect Fit+ Product Details Size 16" x 30" or 30" x 16" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 17. 75" X 31. 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