The Kalahari boasts a high level of comfort and great functionality. A back strap sandal with hook-and-loop fasteners and a PU/TPU outsole added for increased traction and durability. The Cross Country version is designed for Birkenstock fans who are active and looking for some extra grip to their sandals. The Cross Element Adventure version goes a step further by making the style water-ready, so whether you're trekking over rocks or through rivers, your feet will always be comfortable and supported.