This is a Disentanglement puzzle, also known as a rope-and-ring or tavern puzzle. This classic example requires spatial reasoning, patience, and strategic maneuvering rather than force. These puzzles are often made of metal or wood and are popular in brain teaser sets. I would consider this an entry-level puzzle geared to younger children. The average adult should be able to solve it within a few minutes.

Build Instructions: https://www.instructables.com/...

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