4" X 12" Floor Register with Louvered Design - Heavy Duty Rigid Floor Air Supply with Damper & Lever - White 4" X 12" Is The Size For The Duct Opening Measurement Only, Actual Front End Outer Dimensions Are 5.5" X 13.5" - SEE BELOW IN DESCRIPTION HOW TO MEASURE A GRILLE Damper With Lever for Easy Cntrol of Airflow - Lever Is Easily Operated by Foot Rigid Extra Heavy Duty to withstand constant walk on situations - Quality Packaging - Carefully Shrink Wrapped With Cardboard Backing To Prevent Damage In Shipment Smooth Surface Edges - Run Your Fingers Across The Surface To Feel The Smoothness Easy Unrestricted Air Flow For Your HVAC System