Hanayama's Cylinder brainteaser gives you no clues to the solution - and that's part of the fun. The outside of this elegant little knurled cylinder doesn't offer any hints, but we'll give you one: Think about it as though you are cracking a safe. After you separate the cast metal cylinder into its components, can you put it back together again? This cast metal puzzle designed by Vesa Timonen is considered difficulty level 4 (challenging). Measures 4.72'' x 2.99'' x 1.88''. Hanayama is known worldwide for challenging puzzles and quality manufacturing. BePuzzled is more than just jigsaw puzzles - it's puzzle-plus.