OSRAM HPL 575 watts 115 volts Medium Bipin with Heat Sink 300 hours Halogen light bulb "HPL lamps" are a group of stage & studio and architectural lamps 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 G9.5 medium 2-pin bases with heat sinks. The OSRAM 54622 is a high performance HPL 575 that runs on 115V. This lamp features OSRAM’s new UCF (ultra compact filament) design which improves image clarity, light collection, and lamp efficiency.