The Fiat 124 uses the H6024 bulb type for both high beam and low beam headlights across all listed model years, spanning 1976-1983.
The H6024 is an ANSI-standardized sealed beam unit, meaning the lens, reflector, and filament are fused into a single non-serviceable assembly. When the filament fails, the entire unit is replaced rather than an internal bulb.
The H6024 unit measures 7 inches in round format, which is a common standardized size in North American automotive lighting of that era.
The H6024 operates at 12 volts, consistent with the standard electrical systems found in passenger vehicles of that period.
Because the H6024 is an ANSI-standardized type, units from different manufacturers are generally interchangeable as long as they carry the same designation, provided the voltage rating matches.
The identical H6024 specification for both high beam and low beam positions indicates the Fiat 124 uses a dual-headlight arrangement where each sealed beam unit handles a single function rather than a combined unit handling both beams.