INFINITI Q50 Turn Signal Bulb Size

The INFINITI Q50 rear turn signal bulb uses a 7440NA size. The replacement chart covers 2014 to 2018 vehicle 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.

Rear Turn Signal

Years	Bulb Size
2018	7440NA
2014-2016	7440NA

Bulb Specifications

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

Other Locations

Additional Notes

The 7440NA is a single-filament wedge bulb built to the T20 form factor, operating at 12 volts and rated at 21 watts.
The "NA" suffix in the 7440NA designation denotes natural amber glass, meaning the bulb produces an amber output without relying on a colored lens or socket filter.
The 7440NA follows the ANSI standard applicable in the United States and Canada, distinguishing it from regional variants that may share the same base type but differ in color or electrical rating.
The INFINITI Q50 uses the 7440NA for the rear turn signal across the 2014-2016 and 2018 model years.
The T20 wedge base is a push-in connector type with no separate metal pins, which means the bulb is retained and makes electrical contact through the wedge-shaped plastic base itself.
Because the 7440NA incorporates amber glass, substituting it with a clear 7440 variant in the same socket would alter the output color, which may affect compliance with turn signal visibility regulations.
The single-filament construction of the 7440NA means it serves one dedicated function per socket, as opposed to dual-filament T20 variants such as the 7443, which support two brightness levels within a single bulb.
At 21 watts, the 7440NA draws a specific current load that the vehicle's turn signal flasher relay is calibrated to recognize. Substituting a bulb with a significantly different wattage can cause irregular flash rates.