8"W X 8"H [Duct Opening] Aluminum Double Deflection Adjustable Air Supply HVAC Diffuser - [Outer Dimensions: 9.6"W X 9.6"H] Powder Coated + Product Details Size -

+ Product Details Size - 16"w X 28"h is the size for the duct opening measurement only

Think of the diameter as a straight line from one end to the other

Actual Filter Size – 27 3/4"w x 31 3/4" x 1"

+ Product Details Size – 20"w X 25"h is the size for the duct opening measurement only

+ Product Details Size - 10"w X 32"h is the size for the duct opening measurement only

8"W X 8"H [Duct Opening] Aluminum Double Deflection Adjustable Air Supply HVAC Diffuser - [Outer Dimensions: 9.6"W X 9.6"H] Powder Coated + Product Details Size -+ Product Details Size 8"w X 8"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 9. 6" width X 9. 6" height. Design Full Control Vertical Horizontal Air flow Direction. Horizontal blades in the front, Vertical blades in the back, both individually adjustable. High Quality Aluminum The premium durable aluminum will never rust and it will never wear through leaving the material with an elegant,