This fabulous little gadget brings action and animation to any layout. Powerful randomly flashing blue and yellow LEDs produce amazing arc weld effects, used inside an engine shed or garage on your railway. Also brings action/drama to construction site or disaster dioramas. Can a be used by wargamers to simulate muzzle flashes from HMG for instance.The unit is less than an inch long so it is suitable for any scale. No wiring required, runs off a watch battery(installed). A powerful magnet on the base allows unit to be attached to any surface. Even clothing.( Be the centre of attention when you're out clubbing). Try it with the light out, you'll be amazed. I've sold a fair number of these and all buyers were pleased with their purchase. Don't take my word for it. Check my feedback and my other items! Davem.