12"w X 4"h 2-Way-Flat Stamped Steel - Vent Cover - Grille Register - Sidewall or Ceiling - High Airflow w8h8 actual front end outer dimensions

actual front end outer dimensions are approximately 12 5/8" width X 16 5/8" height

actual front end outer dimensions are approximately 38 5/8" width X 20 5/8" height -

+ Product Details Size - 20"w X 22"h is the size for the duct opening measurement only

+ Product Details Size - 12"w X 22"h is the size for the duct opening measurement only

12"w X 4"h 2-Way-Flat Stamped Steel - Vent Cover - Grille Register - Sidewall or Ceiling - High Airflow w8h8 actual front end outer dimensions+ Product Details 12"w X 4"h Is The Size For The Duct Opening Measurement Only, Actual Front End Outer Dimensions Are 13. 75" Width X 5. 75" Height Multi Shutter Damper With Handle Operator Screws Included Quality Packaging Carefully Shrink Wrapped With Cardboard Backing To Prevent Damage In Shipment Carefully Shrink Wrapped With Cardboard Backing To Prevent Damage In Shipment Easy Unrestricted Air Flow For Your HVAC System + Product Description