This month's mystery item is a copper flaring tool, most often used by plumbers and mechanics. You may be more familiar with another version of this tool in which various sizes of holes are spread across a single plane, whereas with this tool, the desired size is dialed in and obtained via a single hole. The purpose of a copper flaring tool is to cut a piece of soft copper tubing, apply a flare fitting, and provide a waterproof seal without soldering. This one was patented in 1946 and is still sold today. To see how it's used, click here.

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