Chain and sprocket drives of one form or another have been driving machines and conveying materials for over a thousand years. The chain manufacturing industry has developed numerous types and sizes of drive chains. Although it is a mature form of power transmission, there are still many industrial applications for which drive chain is suited. It is economical, resistant to shock loads, easy to install, has the ability to transmit high torque, operates in hostile environments, and is efficient. Chain and sprocket drives are highly engineered and manufactured within close tolerances.