The Raspberry Pi GPIO breakout kit comes with a 40 pin ribbon cable, a PCB board, ribbon cable socket and header pins. The PCB has all the pins labeled nicely so you can go forth and build circuits without keeping a pin-out printout at your desk. We think this will make it more fun to expand the Pi and build custom circuitry with it. The breakout kit also prvoide 5V and 3.3V to your breadboard.