Harley-Davidson FXDB Street Bob Headlight Bulb Size
Harley-Davidson FXDB Street Bob headlight bulbs utilize a 9003 bulb size for both high and low beam functions. The replacement chart covers 2007 through 2017 production years with corresponding bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Harley-Davidson FXDB Street Bob uses the 9003 bulb for both the high beam and low beam headlight positions across the 2007-2017 model years.
The 9003 is a dual-filament halogen bulb, meaning a single bulb contains two separate filaments to serve both the high beam and low beam functions within one housing.
The 9003 operates on a 12-volt electrical system and draws 60 watts on the high beam filament and 55 watts on the low beam filament.
The 9003 uses a P43t base, which is a bayonet-style mount with a 43mm flange. This base type is standardized, so physical fitment is consistent across bulbs sharing this designation.
The 9003 is an ANSI-standard designation used in the United States and Canada. It is electrically and physically equivalent to the H4 bulb used under international standards, though the designations differ by market.
Because the high beam and low beam positions on the FXDB Street Bob share the same 9003 specification, a single replacement bulb type serves both functions in the headlight assembly.