Features:

The Pro Micro is similar to the Pro mini except with an ATmega32U4 on board.

4 channels of 10-bit ADC, 5 PWM pins, 12 DIOs as well as hardware serial connections Rx and Tx. Running at 16MHz and 5V.

There is a voltage regulator on board so it can accept voltage up to 9V DC. If you're supplying unregulated power to the board, be sure to connect to the "RAW" pin on not VCC.

Specification:
ATmega32U4 running at 5V/16MHz
On-Board micro-USB connector for programming
4 x 10-bit ADC pins
12 x Digital I/Os (5 are PWM capable)

Package Included:
2 x Pro Micro ATmega32U4 5V 16MHz Development Board Module