The X Pro 100 Ski Boots are consistently the best-selling intermediate-to-advanced alpine boots in the nation, and for good reason -- comfort. In the X Pro 100 from you get all of the performance features you need without having to fight a too-stiff boot. At a silky smooth 100 flex, the X Pro 100 Ski Boots will allow you to venture into deep snow, blast through crud, and rail on the groomers without feeling out of control or getting tossed in the backseat.