Boost rear hubs are designed as precision mountain tools. Featuring one-piece solid axles to provide a stiff hub that will help your suspension perform better and drive every watt of power into the dirt. To thwart mud water and contaminants as you power through rough trails Boost hubs have heavy-duty bearing seals and a threaded driveshell seal ring.Canted flanges for stronger wheel buildsPatented RingDrive system with 72 simultaneously interfaced points of contact for unmatched hub engagementEasily serviceable with a T10 Torx and pick or pen knifeSpecifically designed for "BOOST" 148mm x 12mm axle standardEngineered manufactured and assembled in Portland Oregon USA with King Lifetime Warranty TECH SPECS table{border-collapse:collapse;width:100%;} td{text-align:left;padding:8px;font-weight:350;} tr:nth-child(even){background-color:#f2f2f2} th{background-color:#eb212e;color:white;text-align:left;padding:8px;} .desc .specs-heading{font-size:24px;font-weight:600;padding-top:35px;border-top:3px solid #f0f0f0;display:inline-block;border-bottom:4px solid #eb212e;width:142px;margin:0;} Rear Axle 12mm Thru x 148mm Cassette Body Type Shimano Micro Spline Color Black Skewer Included No Bearing Type Sealed Cartridge Defined Color Black Spoke Interface J-Bend Hub Drilling 28 Hub/Brake Compatibility 6-Bolt Disc