Stem robotics kit - a complete RPI robot kit based on Raspberry Pi. It's Funny to assemble it.(Compatible with RPI 4B/3B/3B+/2B/2B+, Raspberry Pi is not included) Upgrade durable and shatterproof plate. And new style servo, the max Torque of the clutch gear digital servo is up to 1.6kg. It rotates from 0-180 degrees. Easy operation - elaborately-written user Manual and published video for you to easy build your own sensor car robot.