BIOM EVO Trainer is an all-around natural motion running shoe biomechanically designed for comfort and a snug fit. Flexible for ease of movement with light-weight outsole and unlined upper for a natural feel. The uppers are made of strong yak leather for support and added comfort. Created with a low to the ground sole construction for a natural foot position and movement. It's glove-like fit and superb flexibility make it an absolute pleasure to run in, also on longer distances. ideal for both regular and occasional runners.