This is an Oskar van Deventer design which is well known in a square form. This one is round and it makes it just a little bit more fiddly to assemble. There is an added challenge that the “lock”, my own design, must first be removed to be able to disassemble the Domino Tower. Two puzzles in one! It is made in various woods. There are three that have Wrattenswijn (Warthog) tooth in the stand that comes with the puzzle.