Industry Nine Hydra 2 Boost XDRedesigned for durability under the most extreme use, with even faster engagement and less drag Thicker axles, larger beargins, larger pawls with an additional tooth, and a tougher drivering guarantee the Hydra 2 can easily handle the torque of powerf Attributes Axle Type 12mm TA Freehub Body SRAM XD Hub Spacing 148mm Hub Spoke Type J bend Position Rear Rotor Mount 6 bolts