High quality hybrid ceramic bearings with specially designed cups to allow for the smoothest and longest lasting bottom brackets BB30-24 Fits all 24mm spindles on a BB30 frame includes step-down 2-piece non-driveside reducer for use on GXP spindles. See included instructions for spacer reducer configurations alloy cups Choose Road for low friction designed for Road use, or Cross for weather resistant seals designed for MTB, Cyclocross, or Commuting use Choose Road for low friction designed for Road use, or Cross for weather resistant seals designed for MTB, Cyclocross, or Commuting use BB30A-24mm Shim/GXP cross alloy bottom bracket bla Use KB-6806x for BB30 bearings only no cups 2yr warranty with annual bearing service. See KB-009x