A vintage kitchen tool recently sparked online debate after being shared on Reddit, with users puzzled over its sharp, unusual design.

Found in a grandmother’s home, theories ranged from an old can opener to a camping tool.

Eventually, older users identified it as an early can opener—dangerous and hard to use.

Many recalled injuries from its jagged cuts, with one describing the process as punching and levering the lid off step by step. Canned food existed before can openers, often requiring brute force.

In 1858, Ezra Warner created the first opener, mainly used by the military, followed by William Lyman’s safer rotating-wheel design in 1870. Despite improvements over time, some people still use the vintage versions, appreciating their effectiveness despite the risks. The tool now serves as a nostalgic reminder of past kitchen ingenuity—and its hazards.