36" x 32" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Powder-Coat + Product Details Size -

+ Product Details Size - 10"w X 28"h is the size for the duct opening measurement only

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

you can watch this informative video tutorial: How to Measure Your Vent Hole Before Ordering a Grille

10" x 3" Decorative Wood Air Vent HVAC Duct Cover Grille - Polished Finish Red Oak Wood - 2-Way Air Direction

Actual Front End Outer Dimensions Are 16" Diameter

36" x 32" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Powder-Coat + Product Details Size -+ Product Details Perfect Fit & Easy Sizing Designed for a 36" x 32" OR 32" x 36" duct opening (measured at the opening), with actual outer dimensions of 38. 5" W x 34. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 35. 75" x 31. 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