Shimano saint m820 2013 centre lock rear hub both front and rear hubs offer reliability and solid performance with angular contact bearings for total efficiency the rear hubs have a super quick 10 degree engagement for added speed and durability center lock for easy rotor interchangeability and a lighter hub shell one piece axle lightweight strong angular contact bearings balances destructive loads from any direction superior sealing labyrinth and lip seals increase sealing micro ra