18" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter steel + Product Details Size -

+ Product Details Size - 18"w X 28"h is the size for the duct opening measurement only

Actual Front End Outer Dimensions Are 14" Width X 5" Height - SEE IN DESCRIPTION HOW TO MEASURE A GRILLE

actual front end outer dimensions are approximately 8

Actual Filter Size – 27 3/4"w x 7 3/4" x 1"

+ Product Details Size – 24"w X 22"h is the size for the duct opening measurement only

18" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter steel + Product Details Size -+ Product Details Perfect Fit & Easy Sizing Designed for a 18" x 12" OR 12" X 18" duct opening (measured at the opening), with actual outer dimensions of 20. 5" W x 14. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 17. 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