8" x 34" or 34" x 8" Cube Core Eggcrate Return Air Grille sidewall Ideal for Walls & Ceilings:

Ideal for Walls & Ceilings: Designed for seamless installation in standard 18" X 4" duct openings

+ Product Details Size – 36"w X 20"h is the size for the duct opening measurement only

Full Control – Full 190 degrees control of air direction vertically & horizontally

+ Product Details Size - 18"w X 28"h is the size for the duct opening measurement only

8" x 34" or 34" x 8" Cube Core Eggcrate Return Air Grille sidewall Ideal for Walls & Ceilings:+ Product Details Size 8" x 34" or 34" x 8" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 9. 75" X 35. 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