Rossignol Speed 120 Ski Boots - Men's Features: Last - 104 Flex - 120 Shell - Polyurethane Liner - Custome Optisensor T2 Insulation - Thinsulate(TM) Technology: Sensor Matrix - Unique grid positioning on upper and lower shells allows improved shell wrapping, reduces boot weight, and retains high-performance rigidity for power, precision and energy transmission. Easy Entry Insert - A softer plastic insert molded over the instep area allows easy opening of the overlap for more comfortable entry and exit. 104mm Internal Last - The new Internal last features a wider forefoot, toe box, and ankle area while retaining a strong heel pocket for the generous all-day comfort and support Flex Adjustment - Simple rear spine adjustment provides a larger flex range for customized power, performance and comfort