This is an I/O breakout add-on for the micro: bit. This breakout board converts the micro: bit I/O pins into rows of 2.54mm male headers. The VCC & GND are each broken out into a row of 20pins where each individual I/O is broken out into 1 row making it extremely easy to connect sensors, controllers, drivers and many other modules to the micro: bit. The UART and I2C bus is broken out onto 2 separate connectors. Each pin is labeled on the board making it extremely easy to work with.