Here is what Bill has to say about the Visible Burr design: I like to design burrs which are difficult to take apart. This requires irregular notches in the pieces, and I usually like to hide these in the interior of the puzzle. With the Visible Burr, I decided to make all of the notches visible to the solver. Solution of this puzzle can thus be done by analyzing the notches, rather then by using trial-and-error.

The construction of this puzzle is precise yet forgiving; it moves smoothly in nearly every humidity but will be a bit looser in very dry situations.

40 copies made for sale, each signed and dated. This puzzle is shipped assembled.