Description This item is made of plastic and metal material, durable and practical for long time use. Not only as the physics experiment teaching equipment, but also as a decorative ornament for home and office or as gifts for friends or someone who you loves. Features -Color:Assorted.-Material:Plastic, metal.-Size: About13.50X13.50X11.50cm/5.31X5.31X4.52in.- Made of metal and plastic, strong force, durable to use. Great decorations for your office or house.-Experience the visual display of momentum. Can use this in class and share with your friends and family.-Suitable for children to experience the fun of mechanics in the process of playing this fun gadget.-It can be as the decompression toys to relax when learning work fatigue.-Put education in fun, cultivate scientific knowledge. Perfect for any school, or home use.Packing list: 1 x newtons cradle