<ul><li>[Excellent Educational Tool] This excellent educational science tool, showing the pendulum, the law of conservation of momentum and the law of conservation of energy.</li><li>[Decompression ] This is a very interesting decompression . The ball can be used to hit other balls and swing.</li><li>[Premium Material] This alance balls is made of highgrade plastic and sturdy steel balls, and reliable, you can use it for a long time.</li><li>[Good Gift] This balance balls is also a birthday gift , your friends would love it.</li><li>[Widely Use] This balance balls is suitable for home decoration, study room and desk decoration, because it looks beautiful and fashionable.</li></ul><br><br>

Pendulum Ball, Balance Steel Balls Swinging Balls Physics Science Pendulum Ornaments Intelligent Desk Interesting Decompression (7 x 5.8 x 7.1in)