36" x 6" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Return + Product Details Size -

+ Product Details Size - 18"w X 10"h is the size for the duct opening measurement only

This versatile guard features air circulating ports on all four sides to allow proper airflow

Pack of 4 Pieces

Pressure rating: 2300 to 6500 psi

Say goodbye to pest-related worries as the built-in back 1/2" mesh acts as a barrier against unwanted rodents like mice

36" x 6" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Return + Product Details Size -+ Product Details Perfect Fit & Easy Sizing Designed for a 36" x 6" OR 6" x 36" duct opening (measured at the opening), with actual outer dimensions of 36. 5" W x 38. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 35. 75" x 5. 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