Abstract: A battery case retains a battery and is provided with a cable having a removable plug at its distal end, the plug being received in an externally threaded socket member which carries an electric bulb. The socket is threadedly received in a bulb housing of a lamp element member mounted on one side of a bifurcated clip which can be removably installed on a support plate or visor of a hardhat. The battery case has a belt clip which enables the case to be clipped to the belt of a person and rotatably mounting plate on the surface of the case so as selectively to receive the bifurcated clip of the lamp element, on the belt clip or on the plate whereby the lamp element may be rotated with respect to the battery case. In another embodiment, the clip of the lamp element is also removably receivable on a tilt plate carried by a bracket on a head band.