INSMA Motor Smart Robot Car Chassis Kit Speed Encoder Battery Box For Arduino DIY Educational kit for beginners(kid) to get hands-on experience about Robotics & Can extend electronics system like Raspberry Pi Arduino etc to realize function of tracing, obstacle avoidance, distance testing, speed testing, wireless remote control. Smart robot car with code disk, high degree of freedom, ideal for DIY subject, science education, development of hobbies and interest, educational toys for kids. The most economical and newest robot car kit with simple mechanical structure, a nice system and very easy to install. Educational toys, help to improve the ability of children, suitable for young people at key stages of brain development. Size: 20 x 14cm (LxW). Wheel size: 6.5 x 2.7cm (Dia.xH). Motor power supply is 3V ~ 6V