This is a flashlight, a pocket flashlight, the brightest pocket light in the world (I think), at 120 Lumens. It uses a cyan 5 watt Luxeon Star emitter, rated at 120 lumens, a 9 volt battery. The following poem says it all:It sleeps on an aluminum sled, with the 5 watt emitter at the head, The 9 volt battery is in a plastic bed, To the onlookers eyes it is a dread!