The last mechanical puzzle from Bernhard Schweitzer's first consignment to me is really new. It entered the IPP competition last year (2013) under the name of TETRAKIS. It was designed by Yavuz Demirhan and manufactured by Bernhard's company Puzzlewood at a price of Euro 24.- which is a great deal.
My copy is perfectly crafted, the tension to the woods (Maple and Padauk) is absolutely as it should be and it has an awesome fit. I could read on Bernhard's homepage that TETRAKIS is a level 18.104.22.168 puzzle which means 7 moves are necessary to remove the first piece, followed by 3 moves for the second piece and so on. I was a little bit surprised that I could solve TETRAKIS in about 15 - 20 minutes. To take it apart is of course much easier than to reassemble it. The disassembly process therefore took only 2-3 minutes but to bring it back to the initial state was a bit more of a challenge. We are talking about 4 identical pieces that shall fit into the Padauk frame. Self speaking I had the advantage of knowing how I took the puzzle apart which makes the solving process easier. However, the second time I solved it, it took me around 30 mintues for re-assembly. From a difficulty point of view I would rate it similar to THE "BY GEORGE" BURR --> a 6 out of 10.
Again I can recommend TETRAKIS to every kind of puzzler around. There is a fair price tag to the puzzle and the quality is really superb. In addition it looks nice on the shelf (I really like this colour combination). Unfortunately Bernhard is currently out of this puzzle but I am sure he will post information once it is available again.