What is indicated by the letter "N" on a driving license?

The letter "N" on a driving license indicates a tanker vehicle endorsement. This endorsement is specifically required for drivers who operate vehicles designed to transport liquid or flammable materials in bulk, often referred to as tankers. It signifies that the driver has met additional requirements and has received training related to handling these types of vehicles safely.

Having this endorsement is important because tanker vehicles can pose unique safety challenges, including the potential for liquid surges that can affect vehicle control. Therefore, drivers must demonstrate knowledge of the regulations and safe operation practices that are specific to hauling tankers.

The other choices, while relevant to different aspects of driving regulations, do not pertain to the "N" designation on a driver's license. For instance, non-commercial vehicle operation pertains to a broader category of licenses, not necessarily specific to tankers. A requirement for a nervous condition evaluation would be more appropriate with a different designation. Evening driving restrictions, such as those that might be designated for younger or less experienced drivers, would also have a separate identification. Thus, the letter "N" is distinctly associated with the endorsement for tanker vehicles.