The International 150 uses a 198 bulb size for both front and rear turn signal applications. This replacement chart covers vehicle production spanning 1974 to 1975.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The International 150 uses bulb size 198 across all listed positions and years, making it the sole bulb type present in these specifications.
The 198 bulb is an ANSI-standardized type recognized in both the United States and Canada, conforming to a shared North American specification framework.
It is a miniature wedge bulb, classified under the T5 designation, which refers to a tubular glass envelope roughly 5/8 of an inch in width.
The wedge base design means the bulb is held in place by the socket itself rather than by a separate metal base with pins, which affects how it is seated and removed.
The 198 bulb operates at 12 volts and draws 2 watts, placing it at the low end of the power range for automotive signal lighting.
The International 150 (1974-1975) uses the same 198 bulb for both the front and rear turn signal positions, indicating no distinction in bulb type between those two locations.