SainSmart Nano v3.0 black + USB Cable for Arduino Automatic reset during program download. Come with Small mini-B USB for programming. Power OK, blue LED, Green (TX), red (RX) and orange (L) LED Auto sensing/switching power input. Serial monitor ICSP header for direct program download. Standard 0.1" spacing DIP (breadboard friendly). Manual reset switch Power: The 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). The power source is automatically selected to the highest voltage source