18 x 18 Adjustable Air Supply Diffuser -

18 X 18 ADJUSTABLE AIR SUPPLY DIFFUSER - HVAC Vent Duct Cover Sidewall or Cieling - Grille Register - High Airflow - White18w X 18h Is The Size For The Duct Opening Measurement Only, Actual Front End Outer Dimensions Are 19.875 Width X 20 Height - SEE BELOW IN DESCRIPTION How To Measure A GrilleYou may think of grilles and registers as a generic component of the ventilation system in your house. But they are also the most visible representation of you air system. These grilles and registers give you an extra measure of quality that you can point out to your family members and house guests. Some of our best features arent readily apparent, but youll appreciate the benefits over a long period of time. This grille has a high standard of design, production and finish on all products. Every part is hand inspected for quality before it is packaged, no exceptions. No Sharp Surface Edges. Just run your finger along the edge of the top plate and youll find a smooth finished surface. Powder-Coat Finish - Smooth, Shiny, Scratch-Resistant, Beautiful. Looks Like It Was Just Waxed Quality Packaging - Carefully Shrink Wrapped With Cardboard Backing To Prevent Damage In Shipment Easy Unrestricted Air Flow For Your HVAC System How To Measure A Grille Overall Size: Measure the size of the air duct/drywall opening. Do not measure the overall size of the register itself, only measure the hole in the wall/duct. Every grille has a front end frame, that will overlap at wall joint. Total outer size of this grille is; listed size +1.875 at the width, and + 2 at the height. Width vs Height The first number in a grille size, represents the width, the second number represents the height. Example: If your hole is 20 wide by 14 tall, order a 20x14. If your hole is 14 wide by 20 tall, order a 14x20.