The Hanayama Spiral puzzle is unique in its simplicity. It is made of 5 jigsaw-type pieces connected to each other in cyclic fashion. They can slide against each other up and down, but seemingly can never get separated. Even though initially the task looks impossible, playing for a bit with the puzzle will probably give you an idea how to solve it. What is nice about the solution is how simple it looks, just like the design itself. Putting back together Spiral can be much more complicated however, especially if you were not the one to separate it in the first place. Overall a very good puzzle and a highly recommended toy.