26" x 36" or 36" x 26" Cube Core Eggcrate Return Air Grille 14" Round Duct Pipe + Product Details Size –

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

+ Product Details Size - 34"w X 22"h is the size for the duct opening measurement only

+ Product Details Size – 36"w X 18"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 10 5/8" width X 18 5/8" height

26" x 36" or 36" x 26" Cube Core Eggcrate Return Air Grille 14" Round Duct Pipe + Product Details Size –+ Product Details Size 26" x 36" or 36" x 26" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 27. 75" X 37. 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