The International Scout front and rear turn signal bulbs both utilize a 198 size bulb across the model line. The replacement chart covers vehicle production spanning 1961 to 1971.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The International Scout uses the 198 bulb for both front and rear turn signals across the 1961-1971 model years, with all entries designated as Light Duty fitment.
The 198 is an ANSI-standard bulb recognized in both the United States and Canada, operating at 12 volts and 2 watts.
The 198 bulb follows the T5 miniature wedge form factor, which refers to a tubular bulb approximately 5/8 of an inch wide with a wedge-style base that seats directly into a socket without a separate metal base or pins.
At 2 watts, the 198 is a low-output bulb, consistent with its classification as a miniature wedge type rather than a high-intensity signal lamp.
The Light Duty designation present on all International Scout (1961-1971) entries indicates these specifications apply to the standard, non-commercial-grade configuration of the vehicle.
Because the 198 bulb is specified for both the front and rear turn signal positions on the International Scout, both positions share the same socket type and electrical requirements.
The wedge base of the 198 bulb is not interchangeable with bayonet-base or indexed-pin bulb types, even when voltage and wattage ratings are otherwise similar.