It's the Arduino Nano v3.0 without header pins! This version doesn't come with header pins populated so that you can solder in any connector or wire. All of the functionalities are the same as Arduino Nano.Arduino Nano overview:Arduino Nano is a surface mount breadboard embedded version with integrated USB. It is a smallest, complete, and breadboard friendly. It has everything that Diecimila/Duemilanove has (electrically) with more analog input pins and onboard +5V AREF jumper. Physically, it is missing power jack. The Nano is automatically sense and switch to the higher potential source of power, there is no need for the power select jumper.Nano’s got the breadboard-ability of the Boarduino and the Mini+USB with smaller footprint than either, so users have more breadboard space. It’s got a pin layout that works well with the Mini or the Basic Stamp (TX, RX, ATN, GND on one top, power and ground on the other). This new version 3.0 comes with ATMEGA328 which offer more programming and data memory space. It is two layers. That make it easier to hack and more affordable.You end up paying less with Nano than Mini and USB combined!Specifications:Microcontroller Atmel ATmega328Operating Voltage (logic level) 5 VInput Voltage (recommended) 7-12 VInput Voltage (limits) 6-20 VDigital I/O Pins 14 (of which 6 provide PWM output)Analog Input Pins 8DC Current per I/O Pin 40 mAFlash Memory 32 KB (of which 2KB used by bootloader)SRAM 2 KBEEPROM 1 KBClock Speed 16 MHzDimensions 0.70” x 1.70”Power:The Arduino Nano can be powered via the mini-B USB connection, 6-20V unregulated external power supply (pin 30), or 5V regulated external power supply (pin 27).