The Lew electric 812-DFB-NS is a cast iron floor box with a round nickel silver coverThe box was meant to be installed flush in your floor creating a level surface for a nice clean lookInside the floor box is a single 15A duplex outlet with tamper proof plugsYou access the outlet through the 2 screw plugs in the coverThe box is UL listed for the USA and cUL listed for Canada, the receptacle is UL listed making the entire box meet codeThe box has two 3/4 in and two 1/2 in knockouts to connect your wiringThe box was designed for wood floors, it can also be used with carpet by purchasing the sold separately SCF-1 carpet flangeThe box can also be used in post construction concrete floors by coring out a 4.25 in holeThe floor box was designed to provide a flush and seamless look in your floor with versatile mounting options for a variety of applications