Arduino Compatible UNO Rev3 Development Board Microcontroller: ATmega328 1.0 pinout: added SDA and SCL pins that are near to the AREF pin and two other new pins placed near to the RESET pin,the IOREF that allow the shields to adapt to the voltage provided from the board Stronger RESET circuit Flash Memory 32KB (ATmega328) of which 0.5KB used by bootloader Comes with USB cable (100cm)