Sylvania SilverStar Ultra High Performance Halogen Headlight is fashioned for brighter and whiter light. It has dual filament for both high beam and low beam. This operates with internal gas pressure which significantly reduces the rate of tungsten evaporation. Its analogous non-halogen incandescent lamp operates the same filament temperature with greater luminance and efficiency. This combined effect of higher pressure and the halogen cycle give halogen lamp much longer life.