The Hino 258 uses the 9003 bulb size for both high beam and low beam headlights across all model years from 2006-2014.
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 both filaments within a single bulb, it serves the high beam and low beam functions simultaneously, which is why the same bulb size appears in both headlight positions on the 258.
The 9003 uses a P43t base, a bayonet-style mount with a 43mm collar, which determines physical fitment into the headlight housing and is not interchangeable with bases of differing collar sizes.
The 9003 is functionally equivalent to the H4 bulb used in international markets, sharing the same dual-filament halogen construction and P43t base, though the 9003 designation reflects the ANSI classification system rather than the ECE system used for H4.