Wallo APR-0501 Round Access Panel, 4.75 Inch Attractive round access panel provides permanent access to service areas behind drywall ceilings/walls (ductwork air damper controls, electrical junction boxes, plumbing, telephone systems, sprinkler systems, etc.) Easy snap-in installation, pop-out design makes access a breeze Self-contained; requires no framing, screws, latches or fasteners Three convenient sizes (4.75, 7 and 9 diameters); all work in walls or ceilings up to " thick (99% of drywall is or thinner) Satisfies New 2012 Building Codes Requirements