The Triumph Trident high beam and low beam headlight bulbs both utilize a 9003 size. The replacement chart covers vehicle production spanning 1995 to 1998.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Triumph Trident uses the 9003 bulb for both high beam and low beam headlight positions across the 1995-1998 model years.
The 9003 is an ANSI-standard halogen bulb recognized in the United States and Canada, operating on a 12-volt electrical system with a dual-filament design rated at 60 watts for high beam and 55 watts for low beam.
Because the 9003 contains two filaments within a single housing, one bulb serves both beam functions, which is reflected in the Triumph Trident's shared bulb size across both headlight positions.
The 9003 uses a P43t base, a bayonet-style mount with a 43mm collar, which determines physical fitment into the headlight housing.
The 9003 is functionally interchangeable with the H4 bulb, as both share the same P43t base and dual-filament halogen construction, though the 9003 designation follows ANSI standards while H4 follows ECE standards used in Europe.
Substituting a single-filament bulb in either the high or low beam socket of the Triumph Trident would be incompatible with the housing design, as the socket is configured specifically for the dual-filament P43t format.