This small science experiment model, about a physics principle, is made by good quality wood and other assembled parts for primary and middle school students or teachers to make the science class more vivid and improving students' experimental operational skills.             Features:      Easy to assemble and operate, inspire children's interest and curiosity.      Stimulating students' creative thinking and ability by learning physics.      Help teacher to make the science class more lively and interesting.      Small experiments can also consolidate students' mastery of physical knowledge.      Great playing model tools, children can DIY colors on.             Specifications:      Material: wood      Suitable Age: 10+      Knowledge Point: gear drive  Power: 2 * AA batteries (not included)                                                                                                                                                                                                                                                             Item Size: 150 * 100 * 100mm / 5.91 * 3.94 * 3.94in                                                               Package Weight: 112g / 3.95ounce                                                               Package Size: 198 * 300* 15mm / 7.8 * 11.81 * 0.59in