18" x 16" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Aluminum Bar display === 'none') { dd

display === 'none') { dd

"Opposing" back blades

with actual outer dimensions of 34

+ Product Details Perfect Fit & Easy Sizing - Designed for a 8" x 12" or 12" x 8" duct opening (measured at the opening)

18" x 16" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Aluminum Bar display === 'none') { dd+ Product Details Perfect Fit & Easy Sizing Designed for a 18" x 16" OR 16" X 18" duct opening (measured at the opening), with actual outer dimensions of 20. 5" W x 18. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 17. 75" x 15. 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