8"W X 4"H [Duct Opening] 3-Way Aluminum Curved Blade Adjustable Air Supply HVAC Diffuser [Outer Dimensions: 9.75"W X 5.75"H] Material_Aluminum actual front end outer dimensions

actual front end outer dimensions are approximately 20 5/8" width X 28 5/8" height

Complies with industry standards of USA: ASTM D-882

+ Product Description Enhance your HVAC system with our Aluminum Return Filter Linear Bar Grille

+ Product Details Size - 14"w X 18"h is the size for the duct opening measurement only

8"W X 4"H [Duct Opening] 3-Way Aluminum Curved Blade Adjustable Air Supply HVAC Diffuser [Outer Dimensions: 9.75"W X 5.75"H] Material_Aluminum actual front end outer dimensions+ Product Details Size 8"w X 4"h is the size for the duct opening measurement only, actual front end outer dimensions are 9. 75" width X 5. 75" height. Design Individually adjusting curved blades. Multi shutter damper with handle operator to adjust air flow. Screws Included 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 a