34" x 18" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Return + Product Details Size –

+ Product Details Size – 8" x 16" or 16" x 8" is the size for the duct opening measurement only

+ Product Details Size – 22"w X 36"h is the size for the duct opening measurement only

Ideal for Walls & Ceilings: Designed for seamless installation in standard 12" X 10" duct openings

+ Product Details Size – 32"w X 36"h is the size for the duct opening measurement only

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

34" x 18" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Return + Product Details Size –+ Product Details Perfect Fit & Easy Sizing Designed for a 34" x 18" Or 18" x 34" duct opening (measured at the opening), with actual outer dimensions of 36. 5" W x 20. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 33. 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