Black Diamond Factor 130 Ski Boots - Men's Stiffer and more powerful than the Factor 110 Triax Pro Frame with Flex 130 and 20&deg; of resistance-free touring motion Plastic liner tongue for a smooth, evenly distributed flex, plus an extra-wide power strap Power Fit Liner features a 3:1 Boa closure system, warm aerogel-insulated strobel base and articulating zones for touring comfort Equipped with BD Alpine Sole Blocks and compatible with BD AT Sole Blocks with integrated tech inserts (sold separately)