I managed to get one just now. They will likely sell out quickly.
Refurbished Control Ring Mount Adapter EF-EOS R
Mount Adapter Allows EF/EF-S Lens Compatibility with the EOS R Camera. Built-in Control Ring Provides Quick Access to Camera Functions. Exterior Design Matched to EF Lenses. Dust- and Water-resistant. Metal Mount on Both Lens and Camera Sides Provide Rugged Flexibility.
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