2-in-1 Building Experience】 The building blocks can be built into a dinosaur or a crocodile. 【Voice-Activated】 When you clap towards the sensor(at its mouth), the dinosaur or crocodile will move forward or backward，Its mouth will open and close and its tail will whips from side-to-side together.When you clap second time, it stops. 【Infrared Sensing】 When you reach out and let the sensor(at its mouth) sense the heat,it will also move, with the mouth opening and closing, and the tail shaking.When you reach out again, it stops. 【Safety Guaranteed】 The blocks are smoothed,so their smooth surface won't hurt hands,it is safe for children age 3 up.Dangerous for children under 3 yrs because of its small parts. 【Good Choice for Gift】 In the process of children assembling the building blocks, children exercise their skills of comunication, spatial reasoning and hands-on ability. Parents give an appropriate guidance can also improve parent-child relationships.