An electrical box assembly includes an electrical box, a movable partition plate, and a cover having an opening for receiving and supporting an electrical wiring device such as a switch or duplex receptacle. The electrical box has a rear wall with a centrally located emboss having a plurality of screw holes for receiving a ground screw and ground wire. The partition plate has a recess for mating with the emboss and a top end for coupling with the cover member. The partition plate and cover member are adapted for coupling to the electrical box in different orientations so that the partition plate divides the electrical box into substantially equal size compartments for receiving high voltage and low voltage requirements.