The 198 bulb is the sole bulb type listed across all turn signal positions for the International C130, covering both the 1961-1962 model years.
The 198 bulb follows the ANSI standard, meaning it conforms to the American National Standards Institute specifications recognized in both the United States and Canada.
It is a miniature wedge-type bulb, classified under the T5 designation, which refers to a tubular bulb with a wedge base rather than a traditional screw or bayonet fitting.
The T5 wedge base design means the bulb is held in place by the socket itself, with no separate metal base required for electrical contact.
The 198 bulb operates at 12 volts, consistent with the standard automotive electrical systems of that era.
At 2 watts, the 198 bulb produces a relatively low power output, which is characteristic of indicator and signal lighting rather than primary illumination.
The same 198 bulb specification applies to both the front and rear turn signal positions on the International C130, indicating a uniform fitment across signal functions.
The Light Duty classification noted for each entry reflects the vehicle trim or weight rating category to which these specifications apply.