Buick Regal TourX Turn Signal Bulb Size

Buick Regal TourX rear turn signal bulb size 7440 is documented in a chart containing vehicle production years and bulb size specifications. The replacement bulb data covers 2018 to 2020.

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
2018-2020	7440

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Single-filament wedge bulb (T20). 12V, 21W.	7440

Other Locations

Additional Notes

The 7440 bulb is the rear turn signal fitment for the Buick Regal TourX across the 2018-2020 model years.
The 7440 is a single-filament wedge bulb built to the T20 form factor, operating at 12 volts and rated at 21 watts.
As a single-filament type, the 7440 serves one lighting function only, distinguishing it from dual-filament variants such as the 7443, which handles two functions within the same housing.
The 7440 conforms to ANSI standards applicable in both the United States and Canada, indicating regulatory compliance across both markets.
The T20 wedge base design means the bulb is retained by the socket through friction rather than a bayonet or screw mechanism, a common trait in rear lighting assemblies of this era.
The 7440 and 7443 share the same physical T20 wedge base, which means a 7443 bulb can physically seat in a 7440 socket, though the reverse is not always possible due to tab differences on certain socket types.