Are you looking for a kind of educational toy that can also entertain your kids? Our product will be an excellent choice. When feeling tired of studying and working, you can stir balls to hear the clinking sound to ease.Pull back one or more of the balance balls, release them and the same number of balls will swing up on the opposite side. Features - Color: As Shown. - Material: Wood, plastic. - Size: About 14.50X10.00X11.00cm/ 5.70X3.93X4.32in. - This Newton's cradle balance ball toy express your love for science and physics with this decorating your office space. - or more of the balls, release them and the same number of balls will swing on the other side. - When feeling tired of studying and working, you can stir balls to hear the clinking sound to ease. - Suit for both kids and adults, excellent for killing boring time and stress release. - Apply to psychology, teaching tools and furnishings. Frequency swing keeps you in a calm state. Package list: 1 x set of toy