Saturn SC high beam and low beam headlight bulbs both utilize the H4666 bulb size. The replacement chart covers 1991 to 1992 vehicle production years with corresponding bulb specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The H4666 is the sole bulb type listed across all headlight positions for the Saturn SC, covering both the 1991-1992 model years.
The H4666 is a rectangular sealed beam unit, meaning the lens, reflector, and filament are fused into a single assembly. When the filament fails, the entire unit requires replacement rather than an internal bulb swap.
The H4666 operates at 12 volts and conforms to ANSI standards recognized in both the United States and Canada.
The Saturn SC (1991-1992) uses the same H4666 specification for both the high beam and low beam headlight positions, indicating a single sealed beam unit serves dual lighting functions.
Because the H4666 is a sealed beam rather than a bulb-socket design, it is not interchangeable with modern replaceable-bulb housings without modification to the headlight assembly.