【Complete circuit kit】2 battery boxes, 1 switch door, 5 bulbs, 6 wires, 2 circuit boards, complete circuit accessories are included for easy science projects【Fun and safety】 It's a fun and safe physical environment. Learn how to make circuits and make circuits in various ways (series and parallel circuits) to stimulate children's curiosity.【High-quality materials】Made from environmentally friendly materials, high quality and durable, very suitable for children over 4 years old to conduct experiments.【Delivery without battery】Battery is not included. Two AA batteries are required. Children should use it under supervision.【Electronic science toys】Let children and kindergarten students learn physics knowledge and begin to form simple loops, series loops, parallel loops and cultivate hands-on skills . Note: The data are all manual measurement, please allow 1-3cm error, due to the light and display difference, there will be some color difference, depending on the received physical object.