12" x 18" or 18" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 14.5" X 20.5"] Brown ensuring that you find the

ensuring that you find the perfect fit for your ventilation needs

Say goodbye to vibrating louvers - this grille ensures a quiet

+ Product Details Size – 3"w X 10"h or 10"w X 3"h is the size for the duct opening measurement only

And One Towards The Bottom Of The Door

Actual Front End Outer Dimensions Are 16" Width X 5" Height - SEE IN DESCRIPTION HOW TO MEASURE A GRILLE

12" x 18" or 18" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 14.5" X 20.5"] Brown ensuring that you find the+ Product Details Perfect Fit & Easy Sizing Designed for a 12" x 18" or 18" x 12" duct opening (measured at the opening), with actual outer dimensions of 14. 5" W x 20. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 11. 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