A burr puzzle, also known as an interlocking puzzle, consists of notched pieces of wood, plastic or metal that when put together creates a three-dimensional shape. This wood version is pretty simple and therefore relatively easy to make. It consists of 12 pieces of which 11 of are identical. The 12th piece is the similar except that it has a notch cut into the top surface which is the key to the solution.

In addition to the build instructions, I've also include STP and STL files for those inclined to go with the 3D printing route. You could also purchase a similar version from Amazon.

Lastly, it you can't figure it out from the pictures, I've included a video of the solution.

Enjoy making your puzzle!