LIGHTWEIGHT comfort and performanceRubber soleAll the fun, freedom, and benefits of being barefoot, but with the protection and comfort you want in a sport sandal. Xero Shoes come with our 5,000 mile warranty.Perfect if you hike, walk, run, jog, work out, Crossfit, yoga, raft, stand up paddle board, kayak, canoe, fly fish, even run ultra-marathons.Up to 70% lighter than other sport sandals. Only 5.5mm thick, it’s perfect for travel. Flexible enough to roll up and fit in your pack or pocket. Durable enough for wherever the Z-Trek takes you.Zero-drop non-elevated heel for natural posture. 5.5mm non-marking FeelTrue sole. Water resistant. Fast-drying. Great grip and traction. Z-style webbing holds securely, yet slides on and off in seconds.NOTE: For the best chance of a correct fit, please measure your foot: 1) Place a piece of paper on the floor, against a wall; 2) Step on the paper, your heel against the wall; 3) Mark the paper in line with your longest toe; 4) Measure that length with a ruler; 5) Compare that length to the sizing chart (link, above). To REALLY ensure a correct fit, get printable templates of the exact sizes by contacting the Seller.