Harley-Davidson XL1200T SuperLow 1200T Turn Signal Bulb Size

Harley-Davidson XL1200T SuperLow 1200T rear turn signal bulb uses a P21W size. The replacement chart covers 2014 to 2017 production years with corresponding bulb specifications.

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

Rear Turn Signal

Years	Bulb Size
2014-2017	P21W

Bulb Specifications

Description	Bulb Size
ECE standard (Europe & worldwide). Single-filament signalling bulb with BA15s bayonet base. 12V, 21W.	P21W

Other Locations

Additional Notes

The P21W is the rear turn signal bulb used across all listed model years of the Harley-Davidson XL1200T SuperLow 1200T, spanning 2014-2017.
The P21W operates on a 12-volt electrical system and draws 21 watts, which is the standard wattage for single-filament signalling applications in this category.
The bulb uses a BA15s bayonet base, a single-contact fitting where the "s" denotes a single pin offset to one side, ensuring the bulb seats in one orientation only.
The P21W is governed by ECE regulations, meaning it is designed for use in Europe and other markets that follow international lighting standards rather than SAE standards used in North America.
Because the P21W is a single-filament bulb, it serves one function only. It is not interchangeable with dual-filament variants such as the P21/5W, which shares the same base family but carries a second contact pin and an additional filament.
The BA15s base of the P21W is physically similar to the BA15d base found on dual-filament bulbs, but the two are not interchangeable due to differences in pin configuration.