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FIRST ALERT Hardwired Wireless Smoke Alarm with Photoelectric Sensor and Battery Backup, SA521CN-3ST , White - Smoke Detectors - Amazon.com
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First Alert Hardwired Photoelectric Sensor Smoke Detector in the Smoke Detectors department at Lowes.com
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BRK Electronics First Alert SA4919 120V AC/DC Hardwired with 9V Battery Backup Ionization Smoke Alarm (
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