Superlight MTB hubs with a revolutionary drive system 120 tooth pawl mechanism provides instant drive engagement and a freehub sound like no other Micronotch engagement means no noticeable pedal pick-up gap 4 sealed cartridge bearings, aluminum HG freehub body, alloy axle/shell Supadrive 12x142mm axle conversions kits sold separately, HL3182 (12x150mm can be adapted to 12x157mm using HL-3182) International Standard 6bolt disc rotor mount or Center Lock (HL-3087) HG 811sp: Not compatible with HG 11sp road cassettes