DESIGN: Velcro strap + metallic hook enclosure system Mobile Cuff optimizes fore/aft freedom and torsional rigidity for total control IN-SHOE COMFORT: 3M Thinsulate(TM) heat-retaining insulation delivers increased warmth in damp and cold conditions for all-day comfort and warmth Thermoadjustable liners can be heat-molded around your feet for a customized fit and comfort DURABILITY & TRACTION: External 3D plastic reinforcement heel for exception durability A wide Rottefella Nordic BC sole delivers the stability and control for wider skis and varied snow conditions