14" x 28" or 28" x 14" Cube Core Eggcrate Return Air Grille 18in diameter + Product Details Size –

+ Product Details Size – 20"w X 22"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 30 5/8" width X 28 5/8" height

14" Diameter Is The Size For The Duct Opening Measurement Only

[Outer Dimensions: 18

rust-resistant aluminum

14" x 28" or 28" x 14" Cube Core Eggcrate Return Air Grille 18in diameter + Product Details Size –+ Product Details Size 14" x 28" or 28" x 14" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 16. 5" X 30. 5". 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