34" x 16" Cube Core Eggcrate Return Air Filter Grille for 1" Filter w10h10 + Product Details Size -

+ Product Details Size - 28"w X 22"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 10" x 24" or 24" x 10" duct opening (measured at the opening)

Installs Directly On Round & Oval Spiral Duct - No Frames

+ Product Details Size – 28" x 34" or 34" x 28" is the size for the duct opening measurement only

34" x 16" Cube Core Eggcrate Return Air Filter Grille for 1" Filter w10h10 + Product Details Size -+ Product Details Perfect Fit & Easy Sizing Designed for a 34" x 16" Or 16" x 34" duct opening (measured at the opening), with actual outer dimensions of 36. 5" W x 18. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 33. 75" x 15. 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