Nordic Semiconductor nRF51 Development Kit board (PCA20006).

• Debug Interfaces
  JTAG/SW	6-pin 'No Legs' Cable with 20-pin Cortex connector

• Core features
  Other Core Feature	1 x Bluetooth Low Energy (Bluetooth Smart) support
  Other Core Feature	1 x ANT/ANT+ support

• Other
  Crystal Oscillator	16 MHz Crystal Oscillator
  Crystal Oscillator	32.77 KHz Crystal Oscillator
  Other Feature	1 x On-board PCB antenna

• Power
  Power Supply	1.8 V - 3.6 V External power supply
  Power Socket	1 x CR2032 coin cell battery socket

• Display
  LEDs	3 x RGB LEDs

• Controls
  Push-buttons	2 Push-buttons: 2 x User