Locknut system

A locknut system comprising:

• a projecting screw threaded member having a first external thread and an end;
• a nut for mounting on the projecting screw threaded member, the nut having a thread for co-operating with the first thread of the screw threaded member and a first engaging surface;
• a second screw thread formed in a bore which extends from the end of the projecting screw threaded member, the second screw thread being different than the first screw thread;
• a locking member having a screw thread in the form of a projection which may be screwed into the second screw thread of the projecting screw threaded member and having a second engaging surface which can be brought into abutting contact with the first engaging surface on the nut by mating the screw thread of the locking member with the second screw thread of the projecting screw threaded member, wherein the external profile of the second engaging surface is selected from the group consisting of a multi-faceted external profile, a hexagonal external profile and a multi-hexagonal external profile;
• and
• a coupling member for coupling the abutting engaging surfaces of the locking member and the nut to substantially prevent relative rotation there between, wherein one of the locking member and the coupling member carries a snap ring which snaps into engagement with a retaining recess provided on the other of the coupling member and the locking member when the coupling member is mounted in its use configuration, to prevent accidental displacement of the coupling member from the locking member.