Newton's Cradle Dimension Newtons Desktop Gadget 3 LED Colors Change Shine Light Ball HOT Large Newton's Cradle Balance Balls 3 LED Colors Change Shine Lighting Ball Newton's Cradle makes a great desktop gift Item Size: 20cm * 18cm * 15.5cm/ 7.87*7.09*6.10inch Power: 6 x AA Batteries (Not included) Newton's Cradle is a clever device that not only demonstrates a pendulum, but also shows the Laws of Conservation of Momentum and Energy.