16"W X 16"H [Duct Opening] 4-Way Aluminum Curved Blade Adjustable Air Supply HVAC Diffuser [Outer Dimensions: 17.75"W X 17.75"H] Compatible With Duct 10in The integral multi-shutter damper with

The integral multi-shutter damper with a convenient handle operator ensures that you can easily adjust the air volume

+ Product Details Size - 20"w X 6"h is the size for the duct opening measurement only

+ Product Details Size - 8"w X 30"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 42 5/8" width X 12 5/8" height -

16"W X 16"H [Duct Opening] 4-Way Aluminum Curved Blade Adjustable Air Supply HVAC Diffuser [Outer Dimensions: 17.75"W X 17.75"H] Compatible With Duct 10in The integral multi-shutter damper with+ Product Details Size 16"w X 16"h is the size for the duct opening measurement only, actual front end outer dimensions are 17. 75" width X 17. 75" height. Design Individually adjusting curved blades for better air flow control. 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 luxurious touch to any home.