A fuel injection system includes a fuel rail, and a damper that is disposed inside the fuel rail. The damper includes outwardly protruding first barbs formed integrally on one end of the damper and outwardly protruding second barbs formed integrally on an opposed end of the damper. The first barbs and the second barbs each engage the fuel rail inner surface, whereby the damper is located and retained within the fuel rail. The first barbs and the second barbs may be generally triangular in profile and each extend at an acute angle relative to the damper longitudinal axis. In addition, the first barbs and the second barbs are each oriented in the same direction relative to the longitudinal direction, whereby the damper is asymmetric when viewed in side view.