16" x 28" or 28" x 16" Cube Core Eggcrate Return Air Grille Aluminum - Cube Core + Product Details Size -

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

+ Product Details Size – 36"w X 30"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 16 5/8" width X 16 5/8" height

+ Product Details Size – 12" x 16" or 16" x 12" is the size for the duct opening measurement only

+ Product Details Size - 25"w X 12"h is the size for the duct opening measurement only

16" x 28" or 28" x 16" Cube Core Eggcrate Return Air Grille Aluminum - Cube Core + Product Details Size -+ Product Details Size 16" x 28" or 28" x 16" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 17. 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