Hanayama is a Japanese puzzle company that specializes in "Cast metal puzzles" which include reproductions of older designs, and many new puzzles designs by Oskar van Deventer, Akio Yamamoto, Vesa Timonen, JinHoo Ahn, Kennet Walker, and many more. Hanayama rates their puzzles on a scale of 1 through 6, with 6 being the most challenging puzzles in their collection. The first level focuses on fun and developing an understanding of how mechanical puzzles work on a fundamental level, basic ideas that become the building blocks to solving tougher puzzles. Even the simple puzzle designs still take meaningful consideration, but without allowing frustration levels to build. Level 6, on the other hand, is for experienced puzzlers who understand the rules, and now must throw the rulebook out the window. These higher-level puzzles demand more creativity, mixed with strategy and a dash of luck, to be successful. Hanayama tends to design in the realms of disentanglement puzzles, labyrinth puzzles, or puzzle lock mechanisms. Disentanglement puzzles in particular lend themselves well to a metal design because of the precision that can be applied to such durable building material.