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

+ Product Details Size - 30"w X 34"h is the size for the duct opening measurement only

It has an outer surface made of high-quality aluminum foil and an inner surface made of metalized PET with inside high-tensile spring steel wire

or commercial environment

+ Product Details Size – 14"w X 26"h is the size for the duct opening measurement only

16" x 6" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Floor Grille + Product Details Size -+ Product Details Perfect Fit & Easy Sizing Designed for a 16" x 6" OR 6" X 16" duct opening (measured at the opening), with actual outer dimensions of 18. 5" W x 8. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 15. 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 Made