freetronics USB Serial Adapter

Just plug the USB Serial Adapter into a USB port on your computer and provides you with a hardware serial interface: perfect for giving your home-brew Arduino-compatible projects a USB interface compatible with the Arduino IDE. Provides virtual serial port on USB connection; 6-pin header matching FTDI cable pinout; Breakouts for all ATmega16u2 I/O pins; jumper-selectable 3.3V and 5V operation