Hear the doorbell no matter where you are and check who's there with the WHDBI-5C five-channel radio doorbell intercom system. It provides a wireless audio communication link between the doorbell intercom unit (one included, system can support two) and the console station (one included, system can support up to five). The intercom uses digital signals to control the stations and to provide a unique "house code" that prevents other nearby intercoms from accessing your system. Either of two radio frequencies can be selected for the intercoms to further reduce the chance of interference from other units.