The International S110 uses a 198 bulb size for both front and rear turn signal applications. This replacement chart covers 1956 to 1957 vehicle production years.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 198 bulb follows the ANSI standard recognized in both the United States and Canada, placing it within a regulated specification framework common to North American automotive lighting.
The 198 is a miniature wedge-type bulb in the T5 form factor, meaning it uses a wedge base rather than a bayonet or screw fitting, and requires no separate socket retainer to hold it in place.
The 198 bulb operates at 12 volts and draws 2 watts, classifying it as a very low-power light source suited to indicator functions rather than illumination.
The International S110 (1956-1957) uses the 198 bulb in both the front and rear turn signal positions, meaning a single bulb type serves all four turn signal housings on the vehicle.
The Light Duty designation associated with the 198 bulb in these specifications indicates the trim or weight class of the S110 variant for which this fitment applies.
Because the front and rear turn signal positions share the same bulb specification, the 198 is interchangeable across both locations on the International S110 for the covered model years.