12"w X 12"h [Duct Opening] 3-Way Horizontal Fixed Curved Blade Air Supply Diffuser Register Vent Cover Grille [Outer Dimensions: 13.75"W X 13.75"H] Filter Grille + Product Details Size -

+ Product Details Size - 30"w X 8"h is the size for the duct opening measurement only

+ Product Details Size – 32"w X 16"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 28 5/8" width X 32 5/8" height

+ Product Details Size - 32"w X 34"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 26" x 16" OR 16" x 26" duct opening (measured at the opening)

12"w X 12"h [Duct Opening] 3-Way Horizontal Fixed Curved Blade Air Supply Diffuser Register Vent Cover Grille [Outer Dimensions: 13.75"W X 13.75"H] Filter Grille + Product Details Size -+ Product Details Size 12"w X 12"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 13. 75" width X 13. 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