Legend has it that Zhuge Kongming invented a toy according to the principle of Eight Diagrams Metaphysics in the Three Kingdoms Period. It was once widely spread among the people. In recent years, people have gradually attached importance to it. It is good for relaxing body and mind, developing brain and flexible fingers. It is a leisure toy suitable for all ages. Kongming lock looks simple, but in fact, the inside is mysterious and inexhaustible. It is difficult to complete the assembly.