Circuits utilize two lamps, one yellow and one blue, along with a circuit that provides a random flickering effect of the lamps, The result is a very convincing representation of an arc welder in operation. Require a 10-18V AC or DC input for proper operation. Adaptable for all scales. Includes micro-bulbs and is designed for direct viewing in all scales. A small wisp of cotton placed over the lamps will serve to diffuse the light and produce a very realistic smoke effect.