Prime rd030 disc road rear hubthis prime rd030 disc brake rear road hub features a forged alloy 7075 hub body that has been cnc machined to further reduce weight without compromising structural integrity our hubs run on premium japanese sealed cartridge bearings for ultra low friction and superior bearing life the freehub body features a steel construction fop maximum life span and eliminates the potential for damage caused by driving forces from individual sprockets material forged cnc mach