This small metal tool is a vintage can-opening key, sometimes called a winding key or strip key.
Certain food cans were made with a narrow metal strip around the lid or side. The end of that strip was inserted into the slot on the key, and the key was turned to wind the strip around itself. As the strip peeled away, the can opened.
These keys were commonly supplied with products such as corned beef, sardines, coffee, and other specially designed tins. They were not used for every ordinary can, but many households kept one nearby because losing the key could make the package difficult to open.
Although modern pull tabs and standard can openers largely replaced them, these little keys remain a memorable piece of kitchen history.
