Tower of Hanoi 9 Rings Wooden Brain Teaser Puzzle

It consists of three rods, and a number of disks (most common are 7 and9 disks) of different sizes which can slide onto any rod. With three disks, the puzzle can be solved in sevenmoves. The minimum number of moves required to solve a Tower of Hanoi puzzle is2 n 1, where n is the number of disks.

eBay