Featuring Mammut Flextron Technology which supports the natural rolling of the foot and Mammut Georganic 3D Technology for maximum comfort. The Sapuen High boots are a very comfortable pair of boots for all-day wear when out hiking. Waterproof Lightweight 10mm drop Mammut Flextron Technology Mammut Georganic 3D Technology Double Engineered Mesh Upper GORE-TEX Performance Comfort Footwear Lining Vibram Flextron II Outsole