RANGE* Add up to 24 sensors to your SmartSecurity™ System Photoelectric sensor detects smoke UL approved sensor also detects heat from fire Smoke Alarm for SmartSecurity™ Systems 1 Sensor detects smoke or heat 2 Sends signal to system control panel 3 Alarm sounds and system calls up to two phone numbers, telling you the problem Dining Room Kitchen Bedroom Bedroom Bedroom Living Room TV Room Dining Room Kitchen Bedroom Bedroom Bedroom Living Room Dining Room Basement Bedroom Bedroom Living Room =