Incredible physical laboratory equipment aid tool, or as a decoration in your lab,making physical experiment learning more efficient. Explore the decomposition and synthesis of forces, explore the relationship between the distance, speed and time of the particle movement. The instrument consists of a base, a bracket, an iron ring and a steel ball. The product should be stored in a dry, ventilated environment. Good for school teaching tool, learning display, and collectibles, also will be a great addition to your lab supplies.