6" x 18" or 18" x 6" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 8.5" X 20.5"] sidewall + Product Details Size –

+ Product Details Size – 16"w X 22"h is the size for the duct opening measurement only

actual front end outer dimensions are 3"

+ Product Details Size – 16"w X 12"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 32" x 34" Or 34" x 32" duct opening (measured at the opening)

provide precise damper control and superior air dispersion

6" x 18" or 18" x 6" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 8.5" X 20.5"] sidewall + Product Details Size –+ Product Details Perfect Fit & Easy Sizing Designed for a 6" x 18" or 18" x 6" duct opening (measured at the opening), with actual outer dimensions of 8. 5" W x 20. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 5. 75" x 17. 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 Made