Ultra-light backpack dedicated to trail running and rapid elevation change in the mountains. For racers: it manages needs dynamically, with one-point adjustment of harness tension and a stretch insert to add extra volume. Two 500ml soft flasks included. To deal with the intensity of rapid elevation change and trail running, this innovative backpack combines minimalist design, functionality and extreme lightness. To support performance in the mountains, it has an exclusive flat-patterned super-stretch base thats deformation resistant and minimizes overall size, while allowing volume extension with no extra weight. On the move, needs are continuously managed: one-touch adjustment of harness tension for micrometric adjustment of shoulder straps, and a removable back panel to trim weight to a minimum on excursions.