This is the XB24CZ7WIT-004 module from Digi. This is the updated version of the Series 2 (XB24-Z7WIT-004) module. It has an updated firmware which can be configured as router/endpoint/etc. without having to load a different firmware every time. Series 2 modules allow you to create complex mesh networks based on the ZB ZigBee mesh firmware. These modules allow a very reliable and simple communication between microcontrollers, computers, systems, really anything with a serial port! Point to point and multi-point networks are supported. These are essentially the same hardware as the older Series 2, but have updated firmware.
They fully compatible with the Series 2 modules.