A bracket is disclosed for mounting an electrical box on a mounting bar. The bracket comprises a front jaw and a rear jaw. The jaws are movable toward an open position for allowing movement of the bracket relative to the mounting bar and toward a closed position for gripping the mounting bar at a selected position along the mounting bar. The jaws are biased toward the closed position. An electrical box is attached to the front jaw. In one embodiment, the front jaw, rear jaw and a spring for urging the jaws closed are integrally formed from a single piece of sheet metal.