The FlexBox Arena is the new way to interpret a “sports hall” of the latest generation with a modern and attractive design. Equipped with electrical and mechanical systems entirely environmentally friendly, extreme the concept of multi-functionality through the extensive use of partitions and modular grandstands. The arena, in fact, can be used for an infinite number of sports (including basketball, volleyball, tennis, padel, etc…) whether professional or amateur. It is structured to host E-sports competitions, and is also suitable for events, concerts and fairs with the use of state-of-the-art audio-video systems. A strong characterization of the structure is given by the external covering that, among other things, guarantees an optimal climatic and acoustic insulation. The cover, technological and light, is surmounted by photovoltaic panels making it a true example of net zero energy building.