The trick here is that while one can drive a vehicle up to 3.500 kgs here on a regular car license, a tractor-trailor combination like the above with a gross weigth of 7.500 kgs can be driven on a car plus trailer license, which is much cheaper and easier to qualify for than a truck driverīs license.
On europa.eu I found:
Quote:
European Driving Licence: Differences between existing and future legislation
Reference: MEMO/06/143 Date: 27/03/2006
Directive 91/439/EEC
Cars (category B+E): No weight limit for trailers in this category leading to very long and heavy combinations within this category Cars (category B+E)
Future Directive
A weight limit of 3500 kg for trailers in this category is introduced. Combinations with trailers exceeding this weight will fall in category C1+E