12" X 10" [Duct Opening] 2-Way Horizontal Fixed Curved Blade Air Supply Diffuser Register Vent Cover Grille [Outer Dimensions: 13.75"W X 11.75"H] 10" Round Duct Pipe + Product Details Size -

+ Product Details Size - 26"w X 4"h is the size for the duct opening measurement only

Crafted from solid stamped steel

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

This simple adjustment reduces HVAC strain

Actual Filter Size – 23 3/4"w x 21 3/4" x 1"

12" X 10" [Duct Opening] 2-Way Horizontal Fixed Curved Blade Air Supply Diffuser Register Vent Cover Grille [Outer Dimensions: 13.75"W X 11.75"H] 10" Round Duct Pipe + Product Details Size -+ Product Details Size 12"w X 10"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 13. 75" width X 11. 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