24" x 20" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Width_20in + Product Details Size -

+ Product Details Size - 4"w X 36"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 28" x 36" OR 36" x 28" duct opening (measured at the opening)

1/4" - 6518 PSI

Experience enhanced indoor comfort with our 6" Butterfly Damper

this diffuser ensures long-lasting durability and adds a touch of elegance to any space

24" x 20" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Width_20in + Product Details Size -+ Product Details Perfect Fit & Easy Sizing Designed for a 24" x 20" OR 20" x 24" duct opening (measured at the opening), with actual outer dimensions of 26. 5" W x 22. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 23. 75" x 19. 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