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] Powder-Coated + Product Details Perfect Fit

+ Product Details Perfect Fit & Easy Sizing - Designed for a 10" x 36" or 36" x 10" duct opening (measured at the opening)

Actual Filter Size – 23 3/4"w x 33 3/4" x 1"

12" Diameter Is The Size For The Duct Opening Measurement Only

+ Product Details Size - 30"w X 8"h X 2"d (for duct opening measurement only)

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] Powder-Coated + Product Details Perfect Fit+ 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