The EASA PART 66 license
The PART 66 license is the official European document issued by OSAC under the authority of EASA (European Aviation Safety Agency) and allowing any aeronautical technician to operate within a company.
It is obtained within a PART 147 approved organization (standard for EASA aeronautical training centers) by justifying theoretical training and regulatory practices.
There are different types of aeronautical licenses:
Maintenance of turbine aircraft: A1 and B1.1 licenses
Maintenance of piston engine aircraft: A2 and B1.2 licenses
Maintenance of turbine helicopters: A3 and B1.3 licenses
Maintenance of piston engine helicopters: B4 and B1.4 licenses
Avionics: B2 License
Light aviation (less than 2 tonnes): B3 license