When a real locomotive is given a throttle increase there is a lag time until the preselected speed is reached. Like-wise, when braking a life-size, fast moving train it usually takes a mile or so before it stops. But because lightweight model trains wont mimic this delay on their own, we create the momentum or inertia electronically, sometimes referred to as flywheel action. Accutec Technology provides smoother performance and helps maintain the extra power when climbing grades or running over poor track conditions. Advanced slow speed circuitry allows your locomotive to crawl and couple easily.