18" x 20" or 20" x 18" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 18" Round Duct Pipe Vertical blades in the back

Vertical blades in the back

actual front end outer dimensions are approximately 14 5/8" width X 38 5/8" height -

Versatility and Durability: The red oak wood not only adds a touch of warmth and softness to your room but can also be sanded and refinished according to your specific application needs

Its durability and performance contribute to overall comfort

+ Product Details Size - 4"w X 28"h is the size for the duct opening measurement only

18" x 20" or 20" x 18" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 18" Round Duct Pipe Vertical blades in the back+ Product Details Perfect Fit & Easy Sizing Designed for a 18" x 20" OR 20" x 18" duct opening (measured at the opening), with actual outer dimensions of 20. 5" W x 22. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 17. 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