Shimano rs505 cl disc rear road hubthe shimano rs505 cl disc rear road hub is designed for road and cyclo cross riders that are using disc brakes it features improved sealing performance and internal grease sleeves that combine to produce an incredibly smooth and durable hub improved sealing performance through the use of low friction labyrinth and contact seals and an internal grease sleeve designed to be used with either centre lock disc rotor mount for secure hassle free setup or regular r