16" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Insulated Line Set + Product Details Perfect Fit

+ Product Details Perfect Fit & Easy Sizing - Designed for a 30" x 28" OR 28" x 30" duct opening (measured at the opening)

+ Product Details Size – 36"w X 12"h is the size for the duct opening measurement only

Durable Construction – Made from high-quality

+ Product Details Perfect Fit & Easy Sizing - Designed for a 28" x 10" OR 10" x 28" duct opening (measured at the opening)

Actual Filter Size – 7 3/4"w x 5 3/4" x 1"

16" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Insulated Line Set + Product Details Perfect Fit+ Product Details Perfect Fit & Easy Sizing Designed for a 16" x 12" OR 12" X 16" duct opening (measured at the opening), with actual outer dimensions of 18. 5" W x 14. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 15. 75" x 11. 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