The Quadric Cycle Chain is another name for the Four Bar Chain Mechanism. Each of the four links in the four-bar chain mechanism will produce a single turning pair. The lengths of these four linkages can vary. For a four-bar chain mechanism, Grashof’s law states that at least one link must be capable of full rotation, and the sum of the shortest and longest link lengths must be greater than the sum of the other two links. The four bar linkage is a mechanical coupling that can be found in a variety of devices. Locking pliers, bicycles, oil well pumps, loaders, internal combustion engines, compressors, and pantographs are just a few examples.