The patina makes me think the handle is most likely zinc or since plated. Some scratch marks and patina because of its age. I've tried to show everything in the photos butbi can take more if needed. Just under 3" around 7cm when closed and screwed together. Still perfectly function. Because of how the retention mechanism works the corkscrew is a little wobbly but as far as I can tell most of them were because of the design.
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