Hydra

Brand: Industry Nine

CNC-machined rear mountain bike hub made in Asheville, North Carolina, from 7075-T6 aluminium, famous for its 690 points of engagement (115-tooth drive ring plus 6 continuously phased pawls, 0.52 degree engagement). Now sold under the Hydra Classic name (the 870-POE Hydra2 has replaced it as the flagship). Documented version: Boost 148x12, six-bolt disc, 32 holes, SRAM XD freehub. Other options: 28 holes, Centerlock, Shimano HG / Micro Spline / SRAM 9-10-speed freehubs, 12x135/142 axles, 12x150/157 Superboost, fat bike 12x170/177 and 12x190/197.