10"w X 10"h Extruded Aluminum Adjustable Surface Mount Supply Ceiling HVAC Air Grille – Interchangeable: 1-Way, 2-Way, 3-Way or 4-Way - Vent Duct Cover [Outer Dimensions: 11.125" X 11.125"] Fixed Blades with Damper Measure the size of the

Measure the size of the air duct/drywall opening

+ Product Details Perfect Fit & Easy Sizing - Designed for a 6" x 16" or 16" x 6" duct opening (measured at the opening)

+ Product Details Size - 40"w X 20"h is the size for the duct opening measurement only

With precise measurements for seamless integration

10"w X 10"h Extruded Aluminum Adjustable Surface Mount Supply Ceiling HVAC Air Grille – Interchangeable: 1-Way, 2-Way, 3-Way or 4-Way - Vent Duct Cover [Outer Dimensions: 11.125" X 11.125"] Fixed Blades with Damper Measure the size of the+ Product Details Size 10"w X 10"h Is The Size For The Duct Opening Only, Dimensions With Outer End are 11. 125" X 11. 125". Design Re configurable Interchangeable Sections Easily convertible into 1 Way, 2 Way, 3 Way, or 4 Way Just lift sections and rotate to re configure direction. High Quality Aluminum The premium durable aluminum will never rust and it will never wear through leaving the material with an elegant, beautiful, and smooth surface, adds