8" X 4" [Duct Opening] 1-Way Air Vent Adjustable Aluminum Curved Blades Integral Multi-Shutter Damper HVAC Diffuser [Outer Dimensions: 9.75"W X 5.75"H] w24h24 these heavy-duty louvers are ideal

these heavy-duty louvers are ideal for use in attics

Aluminum Return Grille Spec Sheet

actual front end outer dimensions are approximately 20 5/8" width X 22 5/8" height

durable plastic

Actual Filter Size – 33 3/4"w x 31 3/4" x 1"

8" X 4" [Duct Opening] 1-Way Air Vent Adjustable Aluminum Curved Blades Integral Multi-Shutter Damper HVAC Diffuser [Outer Dimensions: 9.75"W X 5.75"H] w24h24 these heavy-duty louvers are ideal+ Product Details Size 8"w X 4"h is the size for the duct opening measurement only, actual front end outer dimensions are 9. 75" width X 5. 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