GraviTrax is a modular, electronic-free interactive track system for designing and building an endless variety of custom marble runs.
Add the Zipline to your GraviTrax contraption and send the marbles rolling. When a marble hits the suspended marble, it's sent racing down the line to hit another marble positioned at the bottom, which is then sent rolling onward.
Turn Newton's Laws of Motion into intense marble run action with the GraviTrax Zipline Accessory!
GraviTrax Accessory - Zipline
Newton't-Cradle-like accessory to add to GraviTrax marble runs