16" x 36" or 36" x 16" Cube Core Eggcrate Return Air Grille 18in diameter but still light and handy

but still light and handy

Design – Full Control Vertical/Horizontal Air flow Direction

Actual Filter Size – 33 3/4"w x 9 3/4" x 1"

actual front end outer dimensions are approximately 12 5/8" width X 18 5/8" height

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

16" x 36" or 36" x 16" Cube Core Eggcrate Return Air Grille 18in diameter but still light and handy+ Product Details Size 16" x 36" or 36" x 16" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 17. 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