This is a U lock which has a mounting brackets and flex cable. The idea is that the U part secures the wheel and the flex cable is used to attach the bike to something. There is a padlock built into the U-lock and there are three keys so you have spares if you need them. The cable is 1200mm so it can easily reach and twist around an adequate area. It is made from a hardened steel shackle with a soft rubber cover so it is really strong and difficult to cut but it is is soft to touch and will not scratch the paintwork on the bike.