The **class B driving license** allows you to drive certain types of motorcycles under specific conditions. According to the information provided, if you have a class B license with an **antiquity of more than 3 years**, you can drive motorcycles that are authorized by the A1 license, but only within the national territory.

- The **A1 license** allows you to drive motorcycles with a **maximum displacement of 125 cubic centimeters** and a **maximum power of 11 kilowatts**. It also allows you to drive motor tricycles with a maximum power of 15 kilowatts.

- Therefore, if your class B license is more than 3 years old, you can drive motorcycles that meet the specifications of the A1 license, that is, low displacement and power motorcycles.

This exception is important because it allows drivers with experience in cars (class B license) to handle small motorcycles without needing to obtain an additional A1 license, as long as they meet the license antiquity requirement.