34" x 36" or 36" x 34" Cube Core Eggcrate Return Air Grille Curved Blade Steel + Product Details Size –

+ Product Details Size – 20"w X 30"h is the size for the duct opening measurement only

High Quality –High quality solid stamped steel with counter-sunk screw holes (screws included) and no sharp edges

+ Product Details Size – 6"w X 12"h is the size for the duct opening measurement only

+ Product Details Outer dimensions: 17

34" x 36" or 36" x 34" Cube Core Eggcrate Return Air Grille Curved Blade Steel + Product Details Size –+ Product Details Size 34" x 36" or 36" x 34" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 35. 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