Programmable XBee Zigbee (Wire Antenna)
Programmable XBee Zigbee (RPSMA Antenna)
The Xbee connects directly with the GPIO interface on the Raspberry Pi. A USB interfacing board can also be used to convert the Xbee into a USB adapter. Available with several different antenna configurations. Nominally, the same device as the XStick, but with additional noise monitoring capability.
There are several variants of this device, but the software is compatible with any with a product code starting with XB24CZ or XB24DZ.