The vital link between your alarm system and the central station is the phone line. Burglars know that by cutting the phone line outside the house, they can defeat the alarm system. However, as an additional option, a radio backup transmitter can be connected to the alarm panel. The establishes a high reliability wireless link between your alarm system and the central station. With radio backup, even if a burglar cuts the phone line, your alarm system will function and contact the central station.