• CLASSIC TOY | Classic desk toy, Perfect gift for anyone!*EDUCATIONAL | Demonstrates Newton's Laws of Motion!*PRESENTATION | This novelty toy is a perfect presentation work! Frame and balls are made of metal. Base is made from pressed wood.*PHYSICS | Own your special piece of science and explore significant values of physics!*SATISFACTION GUARANTEED | Buy from Genius Buy for 100% Satisfaction. This classic desktop display piece has become a must have for office decor. Swing one steel marble back, let it go, and watch as kinetic energy causes the one on the opposite side to swing the same distance! If you're feeling saucy one day, try swinging two or three at once- just don't pass out from the excitement! This desktop display model is a version of Newton's cradle, a device that demonstrates conservation of momentum and energy via a series of identically sized swinging spheres. When one ball on the end is lifted and released, the resulting force travels through the line and pushes the last ball upward. Because it uses Newton's Laws, it was named after Sir Isaac Newton, English physicist, mathematician and astronomer, but was actually invented in 1967 by an English actor.view less