14" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter w20h20 + Product Details Size –

+ Product Details Size – 36"w X 28"h is the size for the duct opening measurement only

Actual Front End Outer Dimensions Are 12" Width X 4" Height - SEE IN DESCRIPTION HOW TO MEASURE A GRILLE

+ Product Details Perfect Fit & Easy Sizing - Designed for a 20" x 28" OR 28" x 20" duct opening (measured at the opening)

Durable stamped steel construction ensures long-lasting performance

actual front end outer dimensions are approximately 18 5/8" width X 22 5/8" height

14" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter w20h20 + Product Details Size –+ Product Details Perfect Fit & Easy Sizing Designed for a 14" x 12" or 12" x 14" duct opening (measured at the opening), with actual outer dimensions of 16. 5" W x 14. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 13. 75" x 11. 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