8" x 22" or 22" x 8" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 10.5" X 24.5"] w6h6 Actual Filter Size – 9

Actual Filter Size – 9 3/4"w x 11 3/4" x 1"

+ Product Details Size – 18" x 24" or 24" x 18" is the size for the duct opening measurement only

+ Product Details Size - 32"w X 30"h is the size for the duct opening measurement only

Optional Butterfly Damper Available At Asin: B007CNEL1W

+ Product Details Size - 4"w X 20"h is the size for the duct opening measurement only

8" x 22" or 22" x 8" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 10.5" X 24.5"] w6h6 Actual Filter Size – 9+ Product Details Perfect Fit & Easy Sizing Designed for a 8" x 22" or 22" x 8" duct opening (measured at the opening), with actual outer dimensions of 10. 5" W x 24. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 7. 75" x 21. 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