The Kalahari futura black birko-flor sandal from Birkenstock - designed to bring Birkenstock comfort and support to your favorite trail and water based activities. These off-road ready sandals feature a direct attach PU footbed, a rugged PU/TPU outsole for added traction and sturdy hook and loop closures for a secure fit. The upper is made from the skin-friendly, hard-wearing synthetic material Birko-Flor.