Aerozine BB-08-RD Road Bottom Bracket Cycling BB/Ceramic Bearing/for Cyclocross CX Fixed Gear Time Trial Triathlon bike/English Threaded BSA/68mm/84g For Shimano Sram Road BSA system use BB Cups L&R bearing cups with CERAMIC bearings (BC-1.37" thread) English threaded 68mm width (BC-1.37x 24T) Weight :84g