10" x 18" or 18" x 10" Cube Core Eggcrate Return Air Grille 14" Round Duct Pipe designed for superior airflow (up

designed for superior airflow (up to 95%) and easy filter access

+ Product Details Size - 6"w X 6"h is the size for the duct opening measurement only

32" x 8" Aluminum Spiral Duct Air Vent Grille Cover - Fully Adjustable Double Deflection HVAC Air Supply

+ Product Details Size - 12"w X 18"h X 2"d (for duct opening measurement only)

10" x 18" or 18" x 10" Cube Core Eggcrate Return Air Grille 14" Round Duct Pipe designed for superior airflow (up+ Product Details Size 10" x 18" or 18" x 10" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 11. 75" X 19. 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