Features Strong Wire: Our newtonian cradle uses high-quality nylon wire, which is strong enough not to break easily. Black Wood Base: The hardwood makes the newtonian cradle align the ball smoothly. Swing time: it only takes 15-25 seconds to align the ball due to air resistance and friction, but it can not achieve a seamless connection between the balls in a vacuum, but it does not affect the effect of the game. More durable and rust-proof: steel frame and 5 high-gloss smooth newtonian steel balls, more durable, easier to carry and store more energy in case of failure. Suitable for: suitable for psychology, teaching tools and furniture. A frequency swing puts you in a state of calm. SpecificationsType: Metal table top, align the ballMedium 14*13.5*11.5, small 9.2*9*7.5Ball diameter: 1.0CMMatterial: metalBackground color: blackSwing time: 15-25 secondsPackage included1 frame with 5 balls1 base