The International A102 uses a 198 bulb size for both front and rear turn signal applications. The replacement chart covers 1957 to 1958 model years with corresponding bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The International A102 uses the 198 bulb for both front and rear turn signals across the 1957-1958 model years.
The 198 is an ANSI-standardized bulb, meaning it conforms to a defined set of electrical and physical specifications recognized across the United States and Canada.
The 198 bulb follows the T5 miniature wedge form factor, a designation that refers to a tubular glass envelope approximately 5/8 of an inch wide with a wedge-style base that seats directly into a socket without a separate metal cap.
The 198 operates at 12 volts and draws 2 watts, placing it among the lower-output bulbs used in automotive signaling applications.
The wedge base design of the 198 means the bulb is retained by the socket itself rather than by a bayonet or screw mechanism, which is a common trait of low-wattage indicator and signal bulbs.
The Light Duty classification noted in the International A102 specifications indicates the vehicle trim or weight rating context in which this bulb fitment applies, distinguishing it from heavier-duty configurations that may carry different requirements.
The front and rear turn signal positions on the International A102 share the same 198 bulb specification for both listed model years, indicating a uniform fitment across all four signal positions on the vehicle.