(side flexing) chains are capable of running on curves. They are constructed of ANSI standard roller links with special diameter pins to provide extra clearance between the pin and the bushing for side flexing and twisting for curved conveyor applications, which include roll conveyors. Side bow chains are also used in power transmission drives where an abnormal chain twist or sprocket misalignment may take place. The attachments for side bow chains are usually available only for inner links and have the same dimensions of the utilized for ANSI standard roller chains.