The rolling stock of the Kelana Jaya Line, in use since the opening of the line in 1998, consists of a fleet of 35 Mark II Bombardier Advanced Rapid Transit (ART) trains with related equipment and services supplied by the Bombardier Group. The ART trains consist of two-electric multiple units, which serve as either a driving car or trailer car depending on its direction of travel. The trains use linear motors and draw power from a third rail located at the side of the steel rails. The plating in between the running rails is used for accelerating and decelerating the train. The reaction plate is semi-magnetised, which pulls the train along as well as helps it to slow down.