12" x 36" or 36" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Grille actual front end outer dimensions

actual front end outer dimensions are approximately 12 5/8" width X 38 5/8" height

Efficient Airflow Design: The slots are meticulously angled to diversify airflow in two directions

Actual Filter Size – 17 3/4"w x 7 3/4" x 1"

this thermostat guard is the perfect solution for safeguarding your temperature controls

12" x 36" or 36" x 12" 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 12" x 36" or 36" x 12" duct opening (measured at the opening), with actual outer dimensions of 14. 5" W x 38. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 11. 75" x 35. 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