What kind of driver's license is needed to drive only a tractor head?

[LePenelope]

To drive only a tractor head, an A2 driver's license is required. Below is relevant information about the A2 driver's license: 1. Overview: The A2 license allows the holder to operate tractor-trailers. With a valid A2 license issued by the Chinese public security traffic management authorities, one can drive heavy and medium-duty full trailers and semi-trailers, as well as vehicles permitted under B1, B2, C1, C2, C3, C4, and M licenses. 2. Notes: The A2 license specifically covers tractor-trailers, which can tow heavy and medium-duty full or semi-trailers. Trailers are divided into two types: full trailers and semi-trailers. A full trailer bears its total weight independently, while a semi-trailer shares part of its total weight with the tractor. Only drivers with an A2 license can operate such tractor-trailers; even those with an A1 license are not permitted to drive them.