The receiver which comes with the Rodann Driveway Alarm System is capable of receiving and distinguishing signals from four (4) different sensor/transmitters and has a 12V Output for activating an accessory when an alarm signal is received! It also comes with a built in LED Digital Counter letting you keep track of your visitors/customers and allowing you to check if an alarm was sent while you were away. The receiver has four (4) different chime sounds which can be used to distinguish between four (4) different sensors and zones!