Smoke Detector, Hardwired Interconnected Smoke Detectors, Smoke Alarm with Replaceable 9V Battery, Interconnects Up to 12 Fire Alarms Smoke Detectors, Photoelectric Fire Alarm with Test/Silence Button - Amazon.com
X-Sense to Unveil XS01-WR Wireless Interconnected Smoke Alarm | PRUndergroundPRUnderground
First Alert Compatibility: Ways to Interconnect Smoke and/or CO Alarms