Roof bars removed from Mazda 6, comes with keys. The mount in your image is a Thule fixed-point (screw-in) setup, not a clamp-on type. The visible threaded bolt and the base plate with the car silhouette (showing “RR”) are characteristic of Thule Fit Kit 3080 / 3069 / 3101-series, used with the Thule Rapid System 753 or Thule Fixpoint Evo (7107) foot packs. So, what you have there is likely a Thule Fixpoint Kit — the bolts screw directly into factory mounting points on the roof (under small removable covers)
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