Wooden Kongming Lock Puzzle - Size: 2.75" Diameter : Wooden blocks. Kongming lock is a traditional Chinese intellectual toy. It is said that the toy was invented by Zhuge Kongming some 2,000 years ago based on the principles of the eight-diagram metaphysics. It was widely popular among the folks. The concave and convex parts inside the three-dimensional interpolation toy mesh perfectly. Kongming locks come in different shapes and sizes, with different internal structures. But they are usually easy to take apart and difficult to reassemble. In recent years, Kongming lock made a comeback and became a popular toy for all, thanks to its functions of mind-body relaxing, intelligence boosting and making fingers more flexible. The lock may look simple, but it contains lots of mysteries. If you don?t understand how it works, you can hardly put it together.