10"W X 8"H [Duct Opening] 3-Way Aluminum Curved Blade Adjustable Air Supply HVAC Diffuser [Outer Dimensions: 11.75"W X 9.75"H] Fixed Blades with Damper + How To Measure A

+ How To Measure A Round Vent Overall Size:

Actual Filter Size – 13 3/4"w x 15 3/4" x 1"

Actual Filter Size – 31 3/4"w x 13 3/4" x 1"

+ Product Details Size - 20"w X 28"h is the size for the duct opening measurement only

High Quality – Polished pre-finish gloss varnish ready to install - can also be sanded and re-finished according to application needs

10"W X 8"H [Duct Opening] 3-Way Aluminum Curved Blade Adjustable Air Supply HVAC Diffuser [Outer Dimensions: 11.75"W X 9.75"H] Fixed Blades with Damper + How To Measure A+ Product Details Size 10"w X 8"h is the size for the duct opening measurement only, actual front end outer dimensions are 11. 75" width X 9. 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