Gikfun Pro Micro ATmega32U4 5V/16MHz Bootloadered IDE V1.0.3 Module Board Leonardo Development Microcontroller Compatible for Arduino Serial Connection with Pin Header EK1564 ATMega 32U4 running at 5V/16MHz, the maximum voltage allowed on the RAW pin is 9V, 6-7V input recommended Supported under Arduino IDE v1.0.3 On-Board Micro-USB connector for programming Rx and Tx Hardware Serial Connections 4 x 10-bit ADC pins, 12 x Digital I/Os