This is a pair of All Terrain reinforced 4 inch wide tracks for the HD2 Treaded Robot. These are the generation 4 design. They have 4 ply mesh reinforcement, molded rubber with no splice. Different lengths can be ordered.
The InvenSense MPU-6050 sensor contains an accelerometer and a gyroscope in a single chip. It is very accurate, this sensor is used in self balancing robots, drones, smartphones, etc. The sensor uses the I2C-bus to interface with microcontroller.