These are the feet for an Audi roof rail... Which should be compatible with a 2009-2016 Audi A4 Waggon or sedan.
I believe they cost about $200 + tax new.
They were mounted on our 2009 Audi A4 avant.
You can buy lock cores at all seasons rack, so the bars are secure on your vehicle.
These feet fit square bars; Thule or Yakima.