36" x 24" Cube Core Eggcrate Return Air Filter Grille for 1" Filter w14h14 + Product Details Size –

+ Product Details Size – 22" x 32" or 32" x 22" is the size for the duct opening measurement only

75"H – fits a 18" X 6" duct opening

complete with a supplied key

Actual Filter Size – 33 3/4"w x 31 3/4" x 1"

Ideal for Walls & Ceilings: Designed for seamless installation in standard 16" X 4" duct openings

36" x 24" Cube Core Eggcrate Return Air Filter Grille for 1" Filter w14h14 + Product Details Size –+ Product Details Perfect Fit & Easy Sizing Designed for a 36" x 24" OR 24" x 36" duct opening (measured at the opening), with actual outer dimensions of 38. 5" W x 26. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 35. 75" x 23. 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