This plastic lock nut or expandable nut is extensively used by BMW. The part is used on most models since the 1990s and in a wide range of locations including under body shields, door locks, engine management units and wheel arch liners.
Please check the details carefully before you order. Every vehicle has many different clips and fasteners. Even if the ebay compatibility check says these are used on your vehicle, that does not mean that they are the only clip and will be the ones that you need. It is important to check the photo, part number and dimensions before you order.