Which of the following is NOT a type of CDL endorsement?

The correct answer is the option that refers to "Air Brakes." This is not classified as a type of CDL endorsement. Instead, it is a restriction that may be applied to a Commercial Driver’s License. When a driver takes a skills test in a vehicle that is equipped with air brakes, they may receive a separate endorsement allowing them to operate air brake-equipped vehicles. However, if the skills test is conducted in a non-air brake vehicle, the driver may be restricted from driving vehicles with air brakes unless they complete the necessary requirements to get that capability.

In contrast, the other options listed—Tanker, Passenger, and HazMat—are indeed types of endorsements that can be added to a CDL. Each of these endorsements qualifies a driver to operate specific types of commercial vehicles: Tanker endorsements allow the transport of liquids in tank vehicles, Passenger endorsements enable the driving of vehicles designed to carry multiple passengers, and HazMat endorsements are necessary for transporting hazardous materials. Understanding these distinctions helps ensure that drivers are properly licensed for the types of vehicles they operate.