14" x 18" or 18" x 14" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 18" Diameter Actual Filter Size – 31

Actual Filter Size – 31 3/4"w x 21 3/4" x 1"

actual front end outer dimensions are approximately 18 5/8" width X 32 5/8" height -

+ Product Description Enhance your HVAC system's efficiency and your home's aesthetics with our premium aluminum air vent diffuser

Installation Location – Sidewall & ceiling

+ Product Details Size - 30"w X 18"h is the size for the duct opening measurement only

14" x 18" or 18" x 14" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 18" Diameter Actual Filter Size – 31+ Product Details Perfect Fit & Easy Sizing Designed for a 14" x 18" OR 18" X 14" duct opening (measured at the opening), with actual outer dimensions of 16. 5" W x 20. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 13. 75" x 17. 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