16" x 18" or 18" x 16" Cube Core Eggcrate Return Air Grille Compatible With Duct 8in 10"w X 8"h Is The

10"w X 8"h Is The Size For The Duct Opening Measurement Only

75"H – fits a 8" X 4" duct opening

+ Product Details Size - 6"w X 32"h is the size for the duct opening measurement only

and Diffusers

16" x 18" or 18" x 16" Cube Core Eggcrate Return Air Grille Compatible With Duct 8in 10"w X 8"h Is The+ Product Details Size 16" x 18" or 18" x 16" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 17. 75" X 19. 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