22" x 36" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Aluminum Adjustable Curved Blade 14" Diameter Is The Size

14" Diameter Is The Size For The Duct Opening Measurement Only

+ Product Details Size - 36"w X 12"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 20" x 30" OR 30" x 20" duct opening (measured at the opening)

Secure Locking Mechanism – Features a permanently attached eight-tumbler lock with a supplied key for added security

+ Product Details Size - 24"w X 18"h is the size for the duct opening measurement only

22" x 36" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Aluminum Adjustable Curved Blade 14" Diameter Is The Size+ Product Details Perfect Fit & Easy Sizing Designed for a 22" x 36" OR 36" x 22" duct opening (measured at the opening), with actual outer dimensions of 24. 5" W x 38. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 21. 75" x 35. 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