Waveshare ARPI600 IO Expansion Board for Raspberry Pi Model A+/B+/2 B /3 B for Arduino XBee Modules with Various Interface Ease to Use Compatible with Arduino UNO, Leonardo, easy to connect with various Arduino shields XBee connector for connecting various XBee modules Sensor interface for connecting various sensors Onboard USB TO UART for serial port debugging, also can be configured as XBee USB adapter Onboard ADC, 10 bit, 38KSPS, 11 channels (6 channels for Arduino interface, 5 channels for sensors)