Kubota RTV-X1100C Turn Signal Bulb Size

Kubota RTV-X1100C rear turn signal bulb size specifications include P21W and P21/5W options for this utility vehicle model. The replacement chart covers 2015 to 2018 production years with corresponding bulb size data.

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
2017-2018	P21W
2016	P21/5W
2015	P21W

Bulb Specifications

Description	Bulb Size
ECE standard (Europe & worldwide). Single-filament signalling bulb with BA15s bayonet base. 12V, 21W.	P21W
ECE standard (Europe & worldwide). Dual-filament signalling bulb with BAY15d bayonet base. 12V, 21W/5W.	P21/5W

Other Locations

Additional Notes

The P21W bulb appears in the Kubota RTV-X1100C rear turn signal position for the 2015 and 2017-2018 model years, making it the more frequently specified bulb type across this model's listed fitment range.
The P21W is a single-filament bulb rated at 12 volts and 21 watts, built to the ECE signalling standard and fitted with a BA15s bayonet base.
The 2016 model year of the RTV-X1100C rear turn signal uses the P21/5W bulb, which differs from the P21W used in the surrounding years.
The P21/5W carries a dual-filament design rated at 12 volts with two wattage outputs, 21 watts and 5 watts, and uses a BAY15d bayonet base.
The BA15s base of the P21W and the BAY15d base of the P21/5W are not interchangeable. The BAY15d base has two offset locating pins to prevent incorrect installation, while the BA15s base has a single pin, meaning the two bulbs cannot be substituted for one another without a socket mismatch.
The dual-filament nature of the P21/5W means the 2016 RTV-X1100C rear turn signal housing is wired to support two separate circuits, one for the higher-wattage signal function and one for the lower-wattage secondary function, a wiring configuration that differs from the single-circuit setup associated with the P21W years.
Both bulb types conform to ECE regulations, a standard recognized across Europe and numerous other markets worldwide, indicating the RTV-X1100C's lighting components are specified to an internationally recognized signalling norm.