A coupling is a device that connects two shafts or a shaft to a rotating component, rotating together during the transmission of motion and power, and remains disconnected under normal circumstances. It is also sometimes used as a safety device to prevent the connected components from bearing excessive loads, serving as an overload protection. The ZL column pin toothed coupling, with nylon bar connection, offers high torque with low noise, is suitable for high torque and medium to low-speed transmission, and is currently one of the better transmission connection devices domestically. It is widely used in mining machinery, construction equipment, pump types, transmission machinery, and other mechanical industries.