This and fashion z-shape balance ball decoration is a scientific adornment according to the principle of conservation of momentum. The ball can swing about 15s due to air friction. You can put it at desktop for relaxation and aspiration. It is also an educational toy for kids. Features -Color: Silver -Material: Stainless steel, ABS, fishing line -Size: 18.00X11.50X18.50cm/7.07X4.52X7.27inch. - Made of stainless steel and ABS material, bright, sturdy and not easy to be damaged. - And it can play, which can bring you a good visual enjoyment, decorative and funny. - Explain your child that physical knowledge and Newton's story, also help to explore the mysteries of the natural science. - Excellent educational science gadget. Not only demonstrates a pendulum, but also displays the laws of conservation of energy and momentum. - This balance ball craft adorn is a perfect decoration for desks and tables, whether at the office, classroom or at home. Package list: 1 x Adornment