Arduino Pro Mini

ArduinoProMini_Back_3v3ArduinoProMini_Front_3v3

Microcontroller ATmega328
Operating Voltage 3.3V or 5V (depending on model)
Input Voltage 3.35 -12 V (3.3V model) or 5 – 12 V (5V model)
Digital I/O Pins 14 (of which 6 provide PWM output)
Analog Input Pins 6
DC Current per I/O Pin 40 mA
Flash Memory 32 kB (of which 0.5 kB used by bootloader)
SRAM 2 kB
EEPROM 1 kB
Clock Speed 8 MHz (3.3V model) or 16 MHz (5V model)

Sources : https://www.arduino.cc/en/Main/ArduinoBoardProMini