I'm doing a rotor and front wheel bearing replacement in my 300sdl and came across these little copper insert tabs that connect in the center of the axle with a flap that appears to be in contact with the allen head locknut.

What is this copper tab for? Something to do with the ABS? How should I replace these, new ones come with my wheel bearing kit.

Thanks for any help or suggestions

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87 300SDL (115,000mi. 7/1/2008)
03 Jetta Wagon TDI (62,000mi. 7/1/2008)
75 240D(sold, sad to sell it, needed the garage for the SDL!)

Smokey