16"W X 12"H [Duct Opening] Steel Air Vent Return Grille - HVAC VENT DUCT COVER DIFFUSER - [Outer Dimensions: 17.75"W X 13.75"H] Supply Grille you can watch this informative

you can watch this informative video tutorial: How to Measure Your Vent Hole Before Ordering a Grille

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+ Product Details Size - 16"w X 36"h is the size for the duct opening measurement only

+ Product Description Introducing our 18" Wooden Corner Baseboard Grille - a sophisticated addition to elevate your HVAC system and interior decor

and Centralized Air Ducted Units

16"W X 12"H [Duct Opening] Steel Air Vent Return Grille - HVAC VENT DUCT COVER DIFFUSER - [Outer Dimensions: 17.75"W X 13.75"H] Supply Grille you can watch this informative+ Product Details Size 16"w X 12"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 17. 75" width X 13. 75" height. Design Easy unrestricted airflow for your HVAC system 50 angled to provide maximum airflow. High Quality Solid stamped steel with counter sunk screw holes (screws included) and no sharp edges. Powder Coat Finish Smooth, shiny, scratch resistant, beautiful. Looks like it was just