OSRAM HPL 575 watts 230 volts Medium Bipin with Heat Sink 400 hours halogen light bulb "HPL lamps" are a family of stage & studio and architectural bulbs and have been designed to work with ETC Source Four ellipsoidals, followspots, and other fixtures. Though HPL lamps are available in various wattages and voltages they all feature G 9.5 medium 2-pin bases with heat sinks. The OSRAM 54618 is a high performance "HPL 575" that runs on 230V. This lamp features OSRAM’ s new UCF (ultra compact filament) design which improves image clarity, light collection, and lamp efficiency.