6" X 6" [Duct Opening] 3-Way Fixed Curved Blade Air Supply Diffuser Register Vent Cover Grille [Outer Dimensions: 7.75"W X 7.75"H] 18in diameter + Product Details Perfect Fit

+ Product Details Perfect Fit & Easy Sizing - Designed for a 20" x 30" OR 30" x 20" duct opening (measured at the opening)

actual front end outer dimensions are approximately 18 5/8" width X 14 5/8" height -

Actual Filter Size – 21 3/4"w x 19 3/4" x 1"

+ Product Details Size – 6"w X 8"h is the size for the duct opening measurement only

+ Product Details Size – 36"w X 24"h is the size for the duct opening measurement only

6" X 6" [Duct Opening] 3-Way Fixed Curved Blade Air Supply Diffuser Register Vent Cover Grille [Outer Dimensions: 7.75"W X 7.75"H] 18in diameter + Product Details Perfect Fit+ Product Details Size 6"w X 6"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 7. 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 Location