Shimano xt disc hub front m756disc hub with 6 bolt international standard mounting featuring fully serviceable cup and cone bearings for precision and durability features a reliable long lasting disc compatible front hub from a classic atb groupsetstandard six bolt fitting for disc brake rotors the perfect hub for shimano deore xt hydraulic disc brake systemdouble contact sealing shuts out mud and water from bearings to extend their service life and maintain smooth operation in all environment