Disentanglement puzzle

Some sources identify a topologically-equivalent puzzle called the Mystery Key issued by the Peter Pan company in the 1950s.

Normally the puzzle must be solved by disentangling the two pieces without bending or cutting the wires.

[10] Early wire puzzles were made from bent carpenter's nails, horseshoes, or similar material.

[11] A plate-and-ring puzzle usually consists of three pieces: The plate as well as the ring are usually made from metal.

Applying a configuration space with a topological framework is an analytical method to gain insight into the properties and solution of some disentanglement puzzles.