[DIY Physics Kits]: This physics experiment pendulum ball set can enhance children's interest in physics, strengthen their understanding of physics, and improve their hands on and thinking skills. [Educational Tools]: This pendulum experiment equipment is a teaching aid for elementary school mathematics and physics classes, providing a hand on learning experience that can help students better understand abstract in a concrete way. [Quality Material]: The handheld pendulum ball kits is made of iron, ensuring its durability and lifespan. [Product size]: The base size is 16cmx9.5cm and 40cm high, which is compact enough for easy storage, but large enough for practical use. Size: Base:16cmx9.5cm/6.30inchx3.74inch Height:40cm/15.75inch Colour:Black Material:iron Package Contents: 1 * Physics Experiment Pendulum Ball Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.