Ceramicspeed ceramic bottom bracketthis bottom bracket offers extremely low bearing friction and long lifespan the unique ceramicspeed ceramic balls are of the highest achievable quality and out perform everything else in the market the system is so stiff and efficient that additional spacers are not required or supplied with it featuresroad specific68mm shellbsa english threadinguse with 24mm spindle cranksetsceramic bearings aluminium cupsweight 84gbuy ceramicspeed components from chain r