Replacement tip for the main slip ring assembly, the main wear part. IF your slip ring post and socket is not lining up with the bands to the contact points, this could be the issue. check the slot, if it si 1mm or less you are due to replace this part. Replacing this part requires removal and complete disassembly of the communicator post. This is an advanced job, proceed carefully, and try not to perform it on the machine as you run the risk of damaging the top side connections. We are working on replacement plastic rings, but in the meantime be very careful with these as they can be brittle. ohm out every wire before calling the repair done, it is really easy to pull a wire off the ring and cause a short.