10" x 12" or 12" x 10" Cube Core Eggcrate Return Air Grille Compatible With Duct 8in Ideal for Walls & Ceilings:

Ideal for Walls & Ceilings: Designed for seamless installation in standard 12" X 4" duct openings

+ Product Details Size - 25"w X 4"h is the size for the duct opening measurement only

It has an outer surface made of high-quality aluminum foil and an inner surface made of metalized PET with inside high-tensile spring steel wire

actual front end outer dimensions are 3"

Great emphasis has been invested in the design of this product to prevent it from kinking in sharp bends & turns and to hold steady and at full diameter in all applications

10" x 12" or 12" x 10" Cube Core Eggcrate Return Air Grille Compatible With Duct 8in Ideal for Walls & Ceilings:+ Product Details Size 10" x 12" or 12" x 10" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 11. 75" X 13. 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