Heiman Photoelectric Wireless Interconnected Smoke Alarm Detector,10-Year 3 PCS

HEIMAN Wireless Interconnected Smoke Alarm,interlinked Smoke Detector, 10-Year Battery Interlinkable Fire Alarm,EN14604/CE Standard(3 Pcs). a maximum of 40 wireless smoke alarms can be interconnected; wireless technology with over 492 ft (150 m) transmission range (in open air).

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