XBee-PRO 900HP
Long Range 900 MHz OEM RF Module
XBee-PRO 900HP platform features:      
* Superior LOS range of up to 28 miles with high-gain antenna 
* Simplified AT command set and advanced XBee API 
* Over-the-air firmware updates 
* Software-selectable channel mask for interference immunity 
* Advanced sleep modes: sleeping routers, pin sleep, cyclic sleep