The INFINITI M56 front and rear turn signal bulbs both utilize the 7440NA bulb size. The replacement chart covers vehicle production spanning 2011 to 2013.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The INFINITI M56 uses the 7440NA bulb across all three model years (2011-2013) for both front and rear turn signals.
The 7440NA is a single-filament wedge bulb, meaning it produces light through one filament and seats into a wedge-style socket without a separate metal base or bayonet pins.
The T20 designation refers to the bulb's form factor, a standardized wedge base size widely used in automotive turn signal and tail light applications.
The 7440NA operates at 12 volts and draws 21 watts, which is consistent with standard automotive turn signal power requirements.
The "NA" suffix in 7440NA indicates natural amber glass, meaning the amber color is produced by the glass envelope itself rather than by an amber-tinted lens or housing.
The 7440NA conforms to ANSI standards applicable in the United States and Canada, establishing it as a North American market specification.
Because the front and rear turn signals share the same bulb size on the INFINITI M56, a single bulb type services all four turn signal positions on the vehicle.
The 7440 base type is a single-filament bulb, and it is not interchangeable with the 7443, which shares the same wedge base but carries a second filament for dual-function applications such as combined stop and tail light duties.