The Sync binding is Connelly's most technically advanced boot to date. Free Flex technology has synergized the connection between the rider and the ski. The Sync is designed to allow your ski to move the way it is supposed to and remain ultra responsive. Low-profile upper boot is set in an exo-frame with built-in flex points at the arch. In the middle of a turn, the exo-frame flexes with the ski ever so slightly, unnoticeable in your boot but very noticeable in the performance of your ski. Sizes: S(6-7), M(8-9), L(10-11), XL(12-13).