Description: It can stimulate children's interest in learning and curiosity through DIY small production. This toy can exercise children's thinking ability and improve children's practical ability through disassembly and assembly. It is made of good quality electronic component and plastic material, durable to use. The length of this installed product is 5.5centimeter, the width is 5.5centimeter and the height is 14.5centimeter. This toy can guide children to fall in love with science, and let children understand abstract knowledge. It is suitable for kids. Item Name: Earthquake Alarm Toy Material: Plastic,Electronic Component Color: Random Color Battery: 1 x Button Battery (Included) Age Level: 7-14 Years Old Features: DIY, Fun, Educational Size Details: Installed Size: 5.5centimeter x 5.5centimeter x 14.5centimeter/2.17" x 2.17" x 5.71" (Approx.) Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Product Principle: 1: Know the closed circuit: When the small ball suspended in the air vibrates after receiving the vibration, the copper wire will hit the iron ring on the edge, causing the wire to contact the iron ring sheet and form a closed circuit. 2: Understand how earthquakes are formed: The rapid vibration of the earth's surface caused by crustal movement and the vibration caused by the rapid release of energy in the crust, during which shock waves are generated, are also a special form of crustal movement. Package Includes: 1 Set of Earthquake Alarm Toy (Included: Square Base, Button Battery, Button Battery Box, Switch, Short Column, Connector, Wiring Sleeve, Buzzer, Rivet, Pin, Two-Hole Flat Button, Flat Button Pole Piece, Glass Ball, Long Column Wire)