hubs from the 1980's but in a new updated cassette version. GT Set the new hubs up with 

full sealed bearings and 3/8" female axles. GT also has set up an option to include a one

 piece 9t driver for those that wish to run them on bikes with the smaller 25t / 28t sprockets.
RHD 3/8" female axlesFully sealed bearings Include 16t cog or 16t cog & 9t option