Thule products are defined by quality and professionalism on all levels, both in terms of design and technological production process, as well as in terms of testing and innovative development. It is in this spirit that the Swedish parent company manufactures every part of its range of luggage boxes and ski racks, eminent on the world market as the largest and best known manufacturer of luggage boxes and similar car accessories. In the optimization process, the trunk boxes are tested by subjecting them to very strong, artificially produced air currents with the aim of minimizing air friction resistance, wind noise and related vibrations.
The load-bearing capacity officially specified by the company, both for the flag and trunk boxes, is indeed lower than the effective load-bearing capacity supported by the advanced materials from which the products are made: in most cases it is the car's flag that would collapse under the pressure of a higher weight. Many tend to confuse the terms flag carrier and flag carrier boxes, using them as synonyms.