22" x 18" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Fixed Blades with Damper + Product Details Size –

+ Product Details Size – 12"w X 4"h is the size for the duct opening measurement only

Ideal for Walls & Ceilings: Designed for seamless installation in standard 16" X 6" duct openings

+ Product Details Size – 30"w X 20"h is the size for the duct opening measurement only

Heavy Gauge Steel – Heavier gauge than needed

+ Product Details Size – 8"w X 4"h is the size for the duct opening measurement only

22" x 18" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Fixed Blades with Damper + Product Details Size –+ Product Details Perfect Fit & Easy Sizing Designed for a 22" x 18" OR 18" x 22" duct opening (measured at the opening), with actual outer dimensions of 24. 5" W x 20. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 21. 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