16" x 18" or 18" x 16" Cube Core Eggcrate Return Air Grille Powder-Coat fasten the edges to studs

fasten the edges to studs with the provided screws

Actual Filter Size – 33 3/4"w x 31 3/4" x 1"

+ Product Details Size – 14"w X 22"h is the size for the duct opening measurement only

+ Product Details Size – 50"w X 20"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 20 5/8" width X 22 5/8" height -

16" x 18" or 18" x 16" Cube Core Eggcrate Return Air Grille Powder-Coat fasten the edges to studs+ Product Details Size 16" x 18" or 18" x 16" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 17. 75" X 19. 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