Raspberry Pi Serial BoB, Wired

This board is designed specifically for the Raspberry Pi This board breaks out the I2C bus, the two SPI busses, and the UART. This enables you to connect our expansion boards to your Raspberry Pi, to easily interface with the outside world!
Unlike the regular version, this version doesn't plug directly on your Pi, but is connected via a 10cm (~4") ribbon cable. Longer cables are available for a premium.
The default version comes with a strain relief on the Raspberry Pi conenctor, but we can leave this out, saving 5mm in height.

Datasheets:
Documentation for the complete PCB