12"W X 6"H [Duct Opening] 3-Way Aluminum Curved Blade Adjustable Air Supply HVAC Diffuser [Outer Dimensions: 13.75"W X 7.75"H] Powder-Coated + Product Details Size –

+ Product Details Size – 16"w X 6"h is the size for the duct opening measurement only

providing a perfect fit for most standard thermostats

Actual Filter Size – 31 3/4"w x 17 3/4" x 1"

Installs Directly On Round & Oval Spiral Duct - No Frames

+ Product Details Size - 12"w X 8"h is the size for the duct opening measurement only

12"W X 6"H [Duct Opening] 3-Way Aluminum Curved Blade Adjustable Air Supply HVAC Diffuser [Outer Dimensions: 13.75"W X 7.75"H] Powder-Coated + Product Details Size –+ Product Details Size 12"w X 6"h is the size for the duct opening measurement only, actual front end outer dimensions are 13. 75" width X 7. 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