Bill Cutler is a renowned puzzle inventor, expert and collector. He is famous for his comprehensive research and analysis of the burr puzzles. Bill’s words: “The 6-Piece Burr is one of the oldest and best-known burr shapes. I have been interested in 6-piece burrs since I saw my first one in a drugstore window when I was about 12 years old. At first I attempted to determine all the ways one could construct a 6-piece burr using standard 'notchable' pieces, but the job was too large. Many years later, I solved this task using a computer. I was particularly interested in burr puzzles which required many moves to take out the first piece.” In the early 1980's Bill wrote his first program to take apart interlocking puzzles made from cubes, and this led to the 3 year analysis of all 35.5 billion 6-piece burrs. Many of the 6-piece burrs that Bill Cutler Puzzles, Inc. sells are the results of that analysis. Others were designed by humans, with or without the help of computer programs. Cooperating with such prominent craftsmen as Jerry McFarland and Walt Hoppe, Bill Cutler Puzzles, Inc. brings a variety of high-quality and challenging puzzles: 6-piece Burrs, Rectilinear Burrs, Non-Rectilinear Burrs, and Box-Filling Puzzles. Enjoy the challenge, visual appeal and tactile feelings while solving their puzzles!