Luban Lock (鲁班锁), also known as Kongming Lock, is a traditional Chinese folk educational toy allegedly being invented by Zhuge Kongming with Chinese carpenter Lu Ban's techniques.
The concave and convex parts inside the three-dimensional interpolation toy mesh perfectly. Luban locks come in different shapes and sizes, with different internal structures. But they are usually easy to take apart and difficult to reassemble.
Lu Ban lived in the Spring and Autumn period (770-476 BC) and is credited with the invention of the saw, the carpenter’s plane and the ink line.
The interlocking burr puzzle with the simplest construction uses three rods that can be assembled into a three-way cross in which each rod is perpendicular to the other two.
On Oct. 10, 2014, Premier Li Keqiang gave a Luban Lock as a gift to German Chancellor Angela Merkel at a bilateral economic and technological forum during his visit to Berlin, with the hope that the two countries can "solve difficulties with intelligence and expand their future."