10"w X 6"h [Duct Opening] 1-Way Fixed Curved Blade Air Supply Diffuser Register Vent Cover Grille [Outer Dimensions: 11.75"W X 7.75"H] 6" Diameter + Product Details Size -

+ Product Details Size - 20"w X 16"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 18" x 6" OR 6" X 18" duct opening (measured at the opening)

75"H – fits a 16" X 12" duct opening

+ Product Details Size – 34"w X 24"h is the size for the duct opening measurement only

+ Product Details Size - 12"w X 26"h is the size for the duct opening measurement only

10"w X 6"h [Duct Opening] 1-Way Fixed Curved Blade Air Supply Diffuser Register Vent Cover Grille [Outer Dimensions: 11.75"W X 7.75"H] 6" Diameter + Product Details Size -+ Product Details Size 10"w X 6"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 11. 75" width X 7. 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