Arlington Industries FLBR101NL-1  Rectangular Floor Outlet Electrical Box Kit with Brass Metal Cover, 1-Gang, Nickel, 1-Pack Single Drywall Nail-On vapor box for fixtures and devices Vapor boxes mount to wood or steel joists with nails or screws that ship captive Non-metallic, non-conductive For fixtures (round), fan or fixture (bar hanger) and devices (single and multiple gangs) No loose parts- ships with mounting screws or captive nails and installed NM cable connectors with gaskets attached