12" x 28" or 28" x 12" Cube Core Eggcrate Return Air Grille Aluminum 7/8" - 3397 PSI

7/8" - 3397 PSI

Actual Filter Size – 21 3/4"w x 7 3/4" x 1"

+ Product Details Size - 30"w X 8"h is the size for the duct opening measurement only

75"H – fits a 14" X 4" duct opening

12" x 28" or 28" x 12" Cube Core Eggcrate Return Air Grille Aluminum 7/8" - 3397 PSI+ Product Details Size 12" x 28" or 28" x 12" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 13. 75" X 29. 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