18" x 18" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Grille actual front end outer dimensions

actual front end outer dimensions are approximately 32 5/8" width X 20 5/8" height -

Designed for both wall and ceiling applications

+ Product Details Size – 8" x 12" or 12" x 8" is the size for the duct opening measurement only

Installation Location – sidewall and ceiling

18" x 18" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Grille actual front end outer dimensions+ Product Details Perfect Fit & Easy Sizing Designed for a 18" x 18" duct opening (measured at the opening), with actual outer dimensions of 20. 5" W x 20. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 20. 75" x 20. 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 Made from