It is a mechanical tool kit that moves with solar cells. You can freely combine and enjoy 4 types of designs for kids. <br> 1. Design like Solar Dinosaur T-REX. Advance with two legs walking. <br> 2. Run while running the drill ahead of the jet drill. <br> 3. Walk while moving the Solar Hercules angle up and down. <br> 4. Solar Robot T4 This is a robot that moves forward with two legs walking. <br> Tools necessary for the work are nippers and hammers. <br>