Even though I knew it would be a difficult project, I couldn't resist making this puzzle. It's a very unique concept and execution. The acrylic maze piece must be removed, and the three key pieces are simultaneously manipulated to achieve the goal. Very tricky and very interesting looking, this puzzle begs to be solved.
Construction was tricky...the solid side spine and endgrain key pieces were fun to make, but very labor intensive. Fit is excellent; should not have any issues with humidity.