16" x 8" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Curved Blade Steel + Product Details Size –

+ Product Details Size – 10"w X 4"h is the size for the duct opening measurement only

+ Product Details Size - 18"w X 14"h is the size for the duct opening measurement only

+ Product Details Size - 12"w X 32"h is the size for the duct opening measurement only

and squirrels

16" x 8" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Curved Blade Steel + Product Details Size –+ Product Details Perfect Fit & Easy Sizing Designed for a 16" x 8" OR 8" X 16" duct opening (measured at the opening), with actual outer dimensions of 18. 5" W x 10. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 15. 75" x 7. 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