Birkenstock Rio Slim Birko-Flor BlackBirkenstock's Rio model is characterized by the straps, which, unlike the more common Arizona model, wrap around the ankle and thus can not slip off. The model you are looking into right now is a women's model in black with a slim fit. Birkenstock for active useRio Slim has all the features we love in the German brand, but with a little extra touch in the form of the buckle around the ankle. Thanks to it, the Rio model is adapted for a little more activity, and you do not have to worry about the sandal slipping off the foot. As with the Arizona model, the melody is cork oak, durable leather and footbed of the highest quality. Birko-flor - easy-care synthetic materialBirkenstock's own Birko flora is a synthetic material, durable and sensitive to the skin. Birko-flor is a mix of PVC plastic and fleece, which makes the material breathable. This means that your feet are comfortable, whether it is hot or cold. Match your Birkenstock Rio sandalsMatching B