16" x 34" or 34" x 16" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Compatible with Duct 8" while the ingenious dial-controlled damper

while the ingenious dial-controlled damper empowers you to effortlessly regulate airflow using your foot

this solid-base guard ensures long-lasting performance with minimal hassle

+ Product Details Size - 20"w X 12"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 10" x 20" duct opening (measured at the opening)

of up to 300m3/h

16" x 34" or 34" x 16" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Compatible with Duct 8" while the ingenious dial-controlled damper+ Product Details Perfect Fit & Easy Sizing Designed for a 16" x 34" OR 34" X 16" duct opening (measured at the opening), with actual outer dimensions of 18. 5" W x 36. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 15. 75" x 33. 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