The engine of the 11 speed drivetrain is the chain it has been designed to eliminate all friction with the sprockets adjacent to those in operation a special treatment ensure smoothness the thickness is 55 millimetres but the retention force is extremely high thanks to the ultra shift technology the chain uses very light hollow pins without compromising strength it is necessary to use the new ut cn300 tool to fit it for more info on the fitting of campagnolo 11 speed chains please view t