28" x 30" or 30" x 28" Cube Core Eggcrate Return Air Grille Color_R-4.2 Yellow Ring Base Design – Allows

Ring Base Design – Allows for easy installation without removing the thermostat

actual front end outer dimensions are 15

+ Product Details Size - 12"w X 24"h is the size for the duct opening measurement only

Actual Filter Size – 33 3/4"w x 23 3/4" x 1"

or office environments

28" x 30" or 30" x 28" Cube Core Eggcrate Return Air Grille Color_R-4.2 Yellow Ring Base Design – Allows+ Product Details Size 28" x 30 or 30" x 28" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 29. 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