8"W X 6"H [Duct Opening] 3-Way Aluminum Curved Blade Adjustable Air Supply HVAC Diffuser [Outer Dimensions: 9.75"W X 7.75"H] Grille + Product Details Size -

+ Product Details Size - 12"w X 20"h is the size for the duct opening measurement only

Actual Filter Size – 31 3/4"w x 23 3/4" x 1"

+ Product Details Size - 6"w X 14"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 36 5/8" width X 38 5/8" height

6" width X 13

8"W X 6"H [Duct Opening] 3-Way Aluminum Curved Blade Adjustable Air Supply HVAC Diffuser [Outer Dimensions: 9.75"W X 7.75"H] Grille + Product Details Size -+ Product Details Size 8"w X 6"h is the size for the duct opening measurement only, actual front end outer dimensions are 9. 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