The Extralite HyperRear hub is one of the lightest disc hubs ever at 168g. The Hyper Rear hub features front engagment cassette driver that can withstand over a half-ton of chain pull. The front and rear hubs come in at an astonishing 246g, which allows for the building of an exceptionally light wheelset. However, nothing about this hub is micro. The rear hub uses 2- 6803 and 2- 6903 RS bearing, and a 17mm axle. The hub body is 7075TX aluminum, anodized black, with laser etched graphics. The hub flanges utilize a straight pull spoke system to reduce lateral flex and increase torque transmission.
Extralite hubs feature carefully designed rubber o-ring seals and lightweight ratcheting mechanisms which require frequent service to ensure long life and maximum performance. This service is easily performed with simple hand tools. An instruction manual for the HyperRear Disc hub is provided here:http://www.extralite.com/Manuals/HyperRear.pdf
Extralite strongly recommends the use of their Alugrease Super 1 when lubricating the HyperRear's o-rings, bushings, and drive rings.