1 WAY Curved Blade Supply Diffuser for 14x8 Duct Opening, White, Steel 1/2 inch spaced curved fins. Primary use: Side wall and ceiling. Screws are included with the system, standard. All-steel construction. Durable white powder coated. Standard color is white (Ral9016). How To Measure A Grille Always measure the size of the duct opening (the 'hole' in the duct/wall). Do not measure the entire size of the register itself. Size of the grille is; listed size +1.75-inch. Understanding Width & Height In a grille size, the first number always represents the width and the second one is the height. As an Example: If the hole on your wall/duct is 14 inches wide by 8 inches tall, order 14x8 option. For this particular product you're viewing at the moment, the hole on your wall/duct opening should be 14x8 duct opening. Click the 'Add To Cart' button now to order your Air Supply Grille!