Description: 【Product】: This a scientific teaching instrument for electric bell experiments, ideal for middle school physics and elementary science classes. 【Material】: Made of PP and copper enameled wire, physics teaching instrument ensuring and during use. 【Features】: Portable design and compact size, easy to carry and store. A good teaching aid to help teachers explain relevant physical knowledge in class. 【Suitable for 】:Electricity experiment building circuits for kids junior seniors high school students.Promote the students understanding of basic electrics knowledge and their learning effect. 【Educational】: Electric bell experiment ideal learing tool for kids, student, develop practical ability. Specification: Material: PP Size Chart: Length 12cm/4.72inch   Package Includes: 1 Electric Bell Experiment  (3 Pack) Note: 1.This is not infant toy , please take away from children to avoid eating. 2.Please allow slightly errors 1-2cm differences due to manual measurement.