C battery to D battery adapter by pavelkaroukin

I am using this adapter to use extra C batteries I have laying around in our baby swing which uses D batteries. Plan is to use food aluminum foil to make a contact between positive terminals of battery and rely on using spring in battery holder to make a contact with negative terminal. UPDATE 12/24/14: I have changed dimensions of positive side a bit, making it easier to keep foil in place.

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