The Pro Mini is a micro-controller board compatible with Arduino base on the ATmega328.  It has 14 digital input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, an on-board resonator, a reset button, and holes for mounting pin headers.

Specifications:

• Pro Mini 5V/16MHz Compatible with Arduino
• Microcontroller: ATmega328
• Circuit Operating Voltage: 5V
• Clock frequency: 16MHz.
• Digital I/O Pins: 14
• 8 analog input port: A0 ~ A7.
• A pair of TTL level serial port transceiver : RX / TX.
• 6 PWM port: D3, D5, D6, D9, D10, D11.
• Support serial download.