Rolling Swivels: This type of swivel has a cylindrical central section, and a closer look at this design of swivel will reveal that both ends of the wire which form the eye go into the central section of the swivel. This produces a swivel which is both stronger and smaller than a barrel swivel, although they are more expensive to manufacture. The design of rolling swivels means that they also perform better then barrel swivels when under load, with the swivels still able to spin and reduce line twist when placed under considerable pressure. Rolling swivels are usually available in black or nickel plated (silver). A size 1/0 rolling swivel will have a breaking strain of around 120lbs, and a size 6 in excess of 60lbs.