The Lew Electric 812-DFB-A is a UL/cUL listed cast iron floor box with round, screw plug aluminum cover. The unit is designed for flush installation in a wood floor. Installation in carpet or tile floors is also possible with the addition of a flange (see links below). Inside the floor box is a 15A-TR-Duplex receptacle. The cast iron box has both 1/2" and 3/4" threaded conduit openings.