14" x 28" or 28" x 14" Cube Core Eggcrate Return Air Grille w28h28 + Product Details Size -

+ Product Details Size - 18"w X 34"h is the size for the duct opening measurement only

+ Product Details Size - 10"w X 32"h is the size for the duct opening measurement only

Actual Filter Size – 29 3/4"w x 31 3/4" x 1"

improves airflow

actual front end outer dimensions are approximately 20 5/8" width X 14 5/8" height

14" x 28" or 28" x 14" Cube Core Eggcrate Return Air Grille w28h28 + 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