These plastic expanding nuts or plugs are snapped into the door to mount the armrest with screws. By tightening the screws, the nut expands and tightens.
It's just a piece of plastic in which the handle is screwed, you can imagine that when the car ages, and especially when the door closes frequently, the screws lose their grip. When replacing the armrests, we recommend that you also order these plugs immediately,
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