International 1010 front side marker bulbs measure 194 in size, while rear side marker bulbs measure 97 in size. The replacement chart covers 1971 to 1973 production 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 1010 uses two distinct bulb types across its side marker positions: the 194 at the front and the 97 at the rear.
The 194 is an ANSI-standard miniature wedge bulb in the T10 form factor, rated at 12V and 3.78W, and is recognized in both the United States and Canada.
The T10 wedge base of the 194 requires no locking mechanism, as the wedge shape itself secures the bulb within its socket.
The 97 is an ANSI-standard single-filament bulb rated at 12V and 13W, fitted with a BA15s bayonet base, and is also recognized in both the United States and Canada.
The BA15s designation indicates a single-contact bayonet base with a 15mm collar, which is a common base type in automotive rear lighting applications.
The 97 is a variant of the 1156 bulb family. Despite this relationship, the two are not always interchangeable, as physical and electrical differences between variants can affect fitment and circuit compatibility.
The front side marker position on the International 1010 uses the 194 across 1971-1973, with the 1972 and 1971 entries carrying a Light Duty designation.
The rear side marker position uses the 97 across 1971-1973, with all three years carrying a Light Duty designation.
The Light Duty designation present in the specifications indicates a vehicle configuration classification, which may be relevant when confirming correct bulb fitment for a specific truck variant.
The wattage difference between the 194 at 3.78W and the 97 at 13W reflects their respective roles, with the higher-wattage 97 serving the rear marker position where greater light output is typically required.