The INFINITI M37 front and rear turn signal bulbs both require the 7440NA bulb size. The replacement chart covers 2011 through 2013 model 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.
The 7440NA is the sole bulb type specified for the INFINITI M37 across all listed turn signal positions and model years.
The 7440NA follows the ANSI standard, which governs bulb specifications for the United States and Canada markets.
It is a single-filament wedge bulb, meaning it produces light through one filament and uses a wedge-style base rather than a bayonet or screw fitting for retention.
The T20 designation refers to the bulb's envelope size, where the number 20 represents twentieths of an inch, placing this bulb in a mid-range size category common in modern automotive applications.
The natural amber glass construction of the 7440NA produces an amber output directly from the glass rather than relying on a clear bulb behind an amber lens, which is a relevant fitment consideration when replacing into housings designed for this configuration.
The bulb operates at 12 volts and 21 watts, values consistent with standard 12V automotive electrical systems and typical turn signal power draw.
The 7440NA specification applies uniformly to both the front and rear turn signal positions on the INFINITI M37 for the 2011-2013 model years, indicating no positional variation in bulb type across the vehicle.
The 7440 base designation is shared with several related bulb variants, though the NA suffix specifically denotes the natural amber glass version. Substituting a clear 7440 in a housing designed for the 7440NA may alter the output color and could affect compliance with lighting regulations.