10"w X 8"h [Duct Opening] 1-Way Fixed Curved Blade Air Supply Diffuser Register Vent Cover Grille [Outer Dimensions: 11.75"W X 9.75"H] 18in diameter 75"H – fits a 18"

75"H – fits a 18" X 8" duct opening

During summer

+ Product Details Size – 36"w X 6"h is the size for the duct opening measurement only

with actual front end outer dimensions of 6"

+ Product Details Size – 8"w X 4"h is the size for the duct opening measurement only

10"w X 8"h [Duct Opening] 1-Way Fixed Curved Blade Air Supply Diffuser Register Vent Cover Grille [Outer Dimensions: 11.75"W X 9.75"H] 18in diameter 75"H – fits a 18"+ Product Details Size 10"w X 8"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 11. 75" width X 9. 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