This is the Microsoft Arc Wireless Keyboard model J5D-00001. The Microsoft Arc keyboard features advanced 2.4GHz wireless technology for ultra-high-speed wireless performance and an extended operating range. The stowable Nano transceiver can be left plugged into your PC or stowed in the keyboard for your convenience. The Microsoft Arc keyboard features a curved, glossy bezel shape with clean lines to complement your style. Its lightweight and compact body fits wherever you use it.