HG freehub. XD freehub：. Only compatible with XD freehub. MS freehub：. Model: ALPHA HG / XD / MS. 11s 1-2 teeth Ultra high strength steel, hardness 680HV (M8000 hardness 580HV) 3-10 teeth High-strength steel, hardness 680HV (M8000 hardness 500HV) 11 teeth 7075 aluminum alloy, hardness 170HV.
