12" x 34" or 34" x 12" Cube Core Eggcrate Return Air Grille return filter actual front end outer dimensions

actual front end outer dimensions are approximately 12 5/8" width X 38 5/8" height

And One Towards The Bottom Of The Door

One Towards The Top Of The Door

Ideal for Walls & Ceilings: Designed for seamless installation in standard 20" X 4" duct openings

12" x 34" or 34" x 12" Cube Core Eggcrate Return Air Grille return filter actual front end outer dimensions+ Product Details Size 12" x 34" or 34" x 12" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 13. 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