UNIQUE LUMINOUS DESIGNNewtons cradle balls are made of good ABS glass, the unique luminous design concept impresses people, which can well meet your needs. This Newtons Cradle can change the color of the ball itself when it is opened. Newtons cradle pendulum as a sports toy, which can relax and release stress.LONGER SWING TIMEGreat Frame size 5.9 x 4.4 x 5.8 inches. Light up newtons cradle balance balls continue in perpetual motion for 10-20 seconds due to the resistance of the air and friction. It is many methods to play, such as one balls rise up in one side, then let if fall down, or two, or each 2 side rise up one ball, and etc...It's so amazing!FIND FUNClassic Newton's Cradle Balance Balls is a perfect way for kids to learn about conservation of momentum and energy. They are great for psychology, science and physics classrooms and are also great for kids with ADHD or autism. It does not only look great in an office but is also an effective way to relieve stress and frustration for office people.PHYSICS EDUCATION TOOLThis Newtons cradle balance ball Toy is a good practice of physics in action demonstrates the principles of kinetic energy and conservation of momentum. Fine argument of Newton's law of motion and the starting point of physics. For every action there is an equal and opposite re-action. Inspired us to better understand the concept of conservation of momentum.