The world's only 100% waterski-specific releaseable hardshell boot system. Variable retention system binding utilizes a combination of dual spring and quick cam technology to create retention and consistent release. Aerospace 7000 series aluminum EXO frame. Forged aluminum frame tip and tail inserts. Front and rear boot rotation for a natural athletic stance. Infinite fore and aft boot adjustment. Sizes: S/M(7-9), L/XL(10-13).