12" x 28" or 28" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Color_Black + Product Details Size –

+ Product Details Size – 32"w X 8"h is the size for the duct opening measurement only

High diffusion induction rates result in rapid temperature and velocity equalization of the mixed air mass well above the zone of occupancy

Actual Filter Size – 17 3/4"w x 17 3/4" x 1"

+ Product Details Perfect Fit & Easy Sizing - Designed for a 6" x 10" or 10" x 6" duct opening (measured at the opening)

and squirrels

12" x 28" or 28" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Color_Black + Product Details Size –+ Product Details Perfect Fit & Easy Sizing Designed for a 12" x 28" or 28" x 12" duct opening (measured at the opening), with actual outer dimensions of 14. 5" W x 30. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 11. 75" x 27. 75" x 1" Premium Airflow Efficiency High performance cube core eggcrate design allows 95% airflow efficiency, reducing energy costs and maximizing HVAC system lifespan. Durable, Rust Free Aluminum