Replacement bulb for 6 1/2 inch Springer style headlamp for FXWG, Softail and custom use including 5 3/4 inch ribbed style headlamp assembly. Fits FXWG 1980-later, Softail 1984-later, Springer 1988-later and custom applications when a larger headlamp is necessary. 100/55 watt H-4 halogen bulb, 12 volt.