Greenex: Solar & Salt Water 3-In-1 Go Science Kit connects kids to the Environment! With this transforming robot car your kids can have a blast building and playing with their solar and salt water powered creation! This cool robot is 100% battery free. When in robot form, it is powered by salt water, and when it is in racer form, it can be powered by saltwater or solar power with the included solar panel! The Greenex Series is 100% battery-free eco learning fun that connects the environment to amazing science experiments. Smartly designed, each Greenex kit allows kids to snap the pieces together with ease. Simply snap all key components and modules together to start and then pull apart once finished. These kits encourage kids to experiment on their own for additional learning. Best of all, each kit can snap to another to integrate functions and double (triple, quadruple) the fun!