8" X 4" [Duct Opening] 3-Way Fixed Curved Blade Air Supply Diffuser Register Vent Cover Grille [Outer Dimensions: 9.75"W X 5.75"H] Insulated Line + Product Details Size -

+ Product Details Size - 18"w X 28"h is the size for the duct opening measurement only

+ Product Details Size - 22"w X 6"h X 2"d (for duct opening measurement only)

Actual Filter Size – 24 3/4"w x 19 3/4" x 1"

+ Product Details Perfect Fit & Easy Sizing - Designed for a 6" x 10" or 10" x 6" duct opening (measured at the opening)

+ Product Details Size – 34"w X 30"h is the size for the duct opening measurement only

8" X 4" [Duct Opening] 3-Way Fixed Curved Blade Air Supply Diffuser Register Vent Cover Grille [Outer Dimensions: 9.75"W X 5.75"H] Insulated Line + Product Details Size -+ Product Details Size 8"w X 4"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 9. 75" width X 5. 75" height. High Quality High quality steel with counter sunk screw holes (screws included) and no sharp edges. Equipped with a lever for easy airflow adjustment and dampening. Airflow Control Adjustable airflow lever allows precise control over the direction and volume of air. Installation Location