6" x 20" or 20" x 6" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 8.5" X 22.5"] Powder Coated + Product Details Size -

+ Product Details Size - 20"w X 10"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 12" x 28" or 28" x 12" duct opening (measured at the opening)

+ Product Details Size – 12" X 4" is the size for the duct opening (floor/vent hole) measurement only

+ Product Details Size – 15" Corner Baseboard Grille - White - HVAC corner vent cover

ISO Supply Diffusers perform efficiently with air loadings of 6 to 30 air changes per hour (based on 10 ft

6" x 20" or 20" x 6" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 8.5" X 22.5"] Powder Coated + Product Details Size -+ Product Details Perfect Fit & Easy Sizing Designed for a 6" x 20" or 20" x 6" duct opening (measured at the opening), with actual outer dimensions of 8. 5" W x 22. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 5. 75" x 19. 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