It looks to be a double boiler of some sort, but we're not sure what it is.

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It's an egg poacher. Looks like this exact model.
Note that these don't really actually "poach" eggs, the result is more like a coddled egg. They do essentially work like double boilers. |
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If you put a dab of butter in the bottom of the cup and and a raw egg over it, then steam it, you'll have coddled or shired eggs. |
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