The International C1000 uses a 198 bulb size for both front and rear turn signal applications. This replacement chart covers 1963 to 1964 model year data.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 198 bulb is the sole bulb type listed across all turn signal positions for the International C1000, covering both the 1963-1964 model years.
The 198 bulb follows the ANSI standard, meaning it conforms to a recognized North American specification used in both the United States and Canada.
It is a miniature wedge-type bulb, classified under the T5 designation, which refers to a tubular glass envelope approximately 5/8 of an inch wide.
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 is a common trait of low-wattage indicator and signal bulbs.
The 198 bulb operates at 12 volts and draws 2 watts, placing it at the lower end of the power range for automotive signal lighting.
The same bulb size applies to both the front and rear turn signal positions on the International C1000 for 1963-1964, indicating no positional differentiation in bulb specification.
All entries in the specifications carry a Light Duty designation, which reflects the vehicle's classification rather than a variation in bulb type.
Because the 198 is a T5 miniature wedge bulb, it is not interchangeable with bayonet-base or indexed-base bulb types even when voltage and wattage ratings are otherwise similar.