Features: 1Plastic Shell: The shell of this physics science experiment kit is made of premium plastic material, which is durable and not easy to be damaged. 2Hand Cranked: Power generation by hand crank, understand the movement principle of machinery, learn the project of transforming it into power, and cultivate children's hands on ability and scientific interest. 3Use: The motor charges the on board capacitor on the generator set by rotating the handle. Shake the power generation handle to charge for 30 seconds or more, and then the car or boat will travel for 2 to 3 minutes to test the charging effect. 4Practical and Simple: The hand cranked generator toy is practical and simple. It can help children to practice and grow up happily. 5100mAh Lithium Battery: The small boat and racing car have built in 100mAh lithium battery, which has a long battery life. The physics science experiment kit is suitable for people over 6 years old. Package included: 1 x Small Boat&nbsp 1 x Racing Car 1 x Hand&nbspCranked&nbspGenerator&nbsp 1 x Instruction 1 x Propeller&nbsp