Metal Pendulum Balance Ball Small Size Physics Science Accessory Desk Table Decor Game Newtons Cradle Steel Ball Features: Type: Cradle BallNot only shows the pendulum, but also shows the rules for conservation of momentum and energy.Material: Metal, ABSOccasions: office, home, deskFeatures: Creative, room decor, table decorationsSize:9 cm x 9 cm x 7.5 cm , ball diameter: 1 cm / 0.39" (approx.)Notes:1. This product can only hit a few times, not hit all the time, please notice before you buy.2. The color of the item may be different, due to the characteristics of the computer monitor.3. Slight deviations in size due to various manual measurements are possible.Package: 1 * cradle ball