12" x 10" or 10" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 14.5" X 12.5"] Round Damper Ring + Product Details Perfect Fit

+ Product Details Perfect Fit & Easy Sizing - Designed for a 28" x 28" duct opening (measured at the opening)

+ Product Details Size - 28"w X 20"h is the size for the duct opening measurement only

+ Product Details Size – 25"w X 32"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 24 5/8" width X 18 5/8" height

it effectively prevents unauthorized access

12" x 10" or 10" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 14.5" X 12.5"] Round Damper Ring + Product Details Perfect Fit+ Product Details Perfect Fit & Easy Sizing Designed for a 12" x 10" or 10" x 12" duct opening (measured at the opening), with actual outer dimensions of 14. 5" W x 12. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 11. 75" x 9. 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