The Ravensburger GraviTrax POWER Starter & Finish element adds an interactive feature to your marble run. Thanks to a wireless connection, the start element and the finish arena communicate directly with each other. As soon as a rolling marble passes the finish line, the next marble from the starter is automatically sent onto the track. The starter has space for up to seven marbles. This electronic set can be flexibly integrated into existing GraviTrax marble run systems and enables automatic marble sequences for dynamic track layouts.