14" x 8" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Compatible With Duct 10in + Product Details Size -

+ Product Details Size - 18"w X 4"h is the size for the duct opening measurement only

Roundover Beveled Edges

+ Product Details Perfect Fit & Easy Sizing - Designed for a 24" x 36" OR 36" x 24" duct opening (measured at the opening)

Actual Filter Size – 11 3/4"w x 19 3/4" x 1"

Contorl Lever To Adjust Louvers According To Season - Complete Open For Summer To Release The Heat

14" x 8" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Compatible With Duct 10in + Product Details Size -+ Product Details Perfect Fit & Easy Sizing Designed for a 14" x 8" or 8" x 14" duct opening (measured at the opening), with actual outer dimensions of 16. 5" W x 10. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 13. 75" x 7. 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