Harley-Davidson FXSTD Softail Deuce headlight bulbs utilize a 9003 bulb size for both high and low beam functions. The replacement chart covers 2000 to 2007 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 FXSTD Softail Deuce uses the 9003 bulb for both high beam and low beam headlight positions across the 2000-2007 model years.
The 9003 is a dual-filament halogen bulb, meaning a single bulb unit contains two separate filaments to serve both the high and low beam functions within one housing.
The 9003 operates on a 12-volt electrical system and carries a wattage rating of 60W on the high beam filament and 55W on the low beam filament.
The 9003 uses a P43t base, which is a three-pronged bayonet-style mount that physically locks the bulb into the headlight housing and aligns the filaments to the reflector.
The 9003 designation follows the ANSI standard, which applies to the United States and Canada, and defines the bulb's electrical and optical output requirements.
Because the same 9003 bulb specification covers both beam positions on the FXSTD Softail Deuce, only one bulb type is required to service the entire headlight assembly.
The 9003 is electrically and physically equivalent to the H4 bulb used in international markets, though the two designations reflect different regional standards and packaging; substitution between them warrants verification of base fitment and wattage compliance.