International S1853 Back Up Light Bulb Size

The International S1853 back up light utilizes bulb size 1156 for illumination purposes. Data for the specified component covers the period from 1981 through 1989.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
1981-1989	1156

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W.	1156

Other Locations

Additional Notes

The International S1853 uses the 1156 bulb for the back up light across all listed model years, spanning 1981-1989.
The 1156 is a single-filament bulb, meaning it serves one lighting function only, which is consistent with its application in a dedicated back up light position.
The 1156 operates at 12 volts and 21 watts, placing it within the standard low-voltage automotive electrical range.
The bulb uses a BA15s bayonet base, a single-contact bayonet mount with a 15mm base width, which requires a matching socket in the vehicle's light housing.
The 1156 carries ANSI standardization for both the United States and Canada, indicating the specification conforms to a recognized North American technical standard.
Because the 1156 is a single-filament type, it is not interchangeable with visually similar dual-filament bulbs such as the 1157, which shares the same bayonet base style but carries two contact points rather than one.