This is the XBee XB24-Z7CIT-004 module from Digi. Series 2 improves on the power output and data protocol.
Series 2 modules allow you to create complex mesh networks based on the XBee 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 2.5, but have updated firmware.
They will work with Series 2.5 modules if you update the firmware through X-CTU.

Note: If you are looking for a simple point-to-point configuration, you might want to try the Series 1 instead. The Series 2 requires considerable setup and configuration.

Note: Series 1 and Series 2 XBee modules have the same pin-out. However, Series 1 modules cannot communicate with Series 2 modules.

Features:

• 3.3V @ 40mA
• 250kbps Max data rate
• 2mW output (+3dBm)
• 400ft (120m) range
• Built-in antenna
• Fully FCC certified
• 6 10-bit ADC input pins
• 8 digital IO pins
• 128-bit encryption
• Local or over-air configuration
• AT or API command set

Documents:

• Digi XBee Series 2 Page
• Datasheet
• Dimensional Drawings
• Digi Examples and Guides
• X-CTU Software