UYN Sports Man Free Flow Metal Shoes Size 42 men's hemp solesRepels heat. The upper is made using special Argenthon on the outside which reflects heat radiation, ensuring cool feet on hot summer days and giving the shoe a distinctive style. On the inside, the bio-based Natex fibre and hemp sole help to disperse moisture quickly and minimizes unpleasant odors. UYN has eliminated any structural seams, creating a high-performance shoe with the comfort of a sock.