The SYLVANIA Halogen Plus Capsule are long-life lights designed to last up to 6 times longer than standard headlights and are engineered to withstand more road shock and vibration. The SYLVANIA Halogen bulb is unlike conventional tungsten-filament lamps which operate with an internal gas pressure of about one atmosphere. These tungsten-halogen lamps operate with an internal gas pressure of several atmospheres to reduce the rate of tungsten evaporation. The combined effects of higher pressure and the halogen cycle give halogen lamps much longer life than that of comparable non-halogen incandescent lamps operating at the same filament temperatures. This halogen lamp will also operate at higher filament temperatures with greater luminance and efficacy.