Roller chain or bush roller chain is the type of chain drive most commonly used for transmission of mechanical power on many kinds of domestic, industrial, and agricultural machinery, including conveyors, wire- and tube drawing machines, printing presses, cars, motorcycles, and bicycles.

Roller chains are constructed like a typical chain link structure; that is, a series of cylindrical rollers connected by links. A rotating sprocket that is connected to the motor moves the chain. A properly lubricated chain can minimize exposure to the environment and extend product life.