Delivering powerful lighting without increasing glare to on-coming traffic, an advanced H4 halogen bulb and high-sheen metal reflector are combined with advanced optics to provide a more uniform, controlled, and even illumination on the road. These lamps produce a 50 percent more powerful low beam and a 25 percent more powerful high beam than standard halogen sealed beam headlamps. This produces a greater range of vision for the driver, improves driver safety and reduces driver strain and fatigue. And the replaceable-bulb design saves money - no need to replace the entire unit if a bulb goes.