Great classic strobes from Optikenitics! These are the classic ‘White Lightning’ strobe units. These were actually made by Mode Electronics (UK) for Optikinitics. Each unit features a linear Xenon strobe tube that is usually located behind a clear Plexiglas protector but the Plexiglas that was with these units has become discolored and lowers the light output. These classic units can run by themselves or with an optional controller. These are heavy and built to last. Fixtures are fan cooled and will work 110 / 120 volts or 220 / 240 volts. Voltage selector on the rear will let you choose. Great classic strobes made in England.