It is the element that is used to transfer rotational motion between two shafts working on the same axis in mechanics. Couplings can be two-piece or three-piece, or multi-piece depending on the model produced. Having an important role in safe motion transmission in machines; COUPLINGS, which seem to be the simplest element in the system and the cheapest element according to the machine it is attached to; It can become the most expensive element of production if care is not taken in its production, selection and assembly. It causes the machine to stop frequently. The selection, assembly and control of the couplings is extremely important, as the disruption of a link in the production chain will affect the entire system in all machine works. Due to the mistakes made here, there are production interruptions in the enterprises and the losses increase. Couplings that cannot meet any irregularity are called rigid couplings, and those that do are called flexible couplings. Couplings that provide flexibility by means of an elastic element are also called Elastic Couplings.