The Shimano 7900 rear hub features a titanium freehub body compatible with Shimano 10, 9, and 8 speed as well as SRAM 10 speed. It has an updated design with an added no-tool "digital click" bearing adjustment nob. A well-sealed, traditional ball bearing design means it is full serviceable. Anyone who has serviced Dura-Ace hubs has likely found the grease good as new because the seals are so effective. The hub has an oversize aluminum axle for stiffness and light weight. Includes a Dura-Ace skewer.