The all new, state-of-the-art DB200 doorbell signaler require no wires and can be installed in seconds. The SA-DB200 is not triggered by sound, so annoying false alarms are a thing of the past. Other advanced features include: selectable number of flashes (5 or 10), different flash code for front door, rear door, or intercom (requires additional sensor, sold separately), and a built-in chime for hearing members of the family (can be turned off). The DB200 has a built-in outlet to flash an attached lamp and it sends a signal to all Sonic Alert remote receivers. The DB200 has the additional feature of being a telephone signaler. Just plug the phone cord into a modular telephone jack.