EZ-FLO 61665 Steel Sidewall and Ceiling Return Air Filter Grille, 16" x 20" White FINISH: White Powder-Coated Smooth Finish quickly updates any room or office DIMENSIONS: Duct opening measures 16-inch x 20-inch, and the outer dimension measures 17-3/4-inch x 21-3/4-inch MATERIAL: All steel construction; high-impact, heavy-duty steel makes this air vent filter grille highly durable CONTENTS: This package includes a kit of screws to make installation easy and efficient EASY INSTALLATION: This return filter grille can be installed on the sidewall or ceiling without any hassle to ensure maximum airflow