8" X 4" [Duct Opening] 3-Way Air Vent Adjustable Aluminum Curved Blades Integral Multi-Shutter Damper HVAC Diffuser [Outer Dimensions: 9.75"W X 5.75"H] Color_Black Design – Fixed Hinged for

Design – Fixed Hinged for easy filter change & cleaning - uses a 1" thick filter

Actual Filter Size – 21 3/4"w x 11 3/4" x 1"

it ensures long-lasting performance in both residential and commercial settings

With a 6" diameter for the duct opening measurement

8" X 4" [Duct Opening] 3-Way Air Vent Adjustable Aluminum Curved Blades Integral Multi-Shutter Damper HVAC Diffuser [Outer Dimensions: 9.75"W X 5.75"H] Color_Black Design – Fixed Hinged for+ 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