Siterwell GS562A Hardwired Interconnected Smoke Detector

Wired interconnection: Up to 12 alarms can be connected. It is more accurate and stable than wireless interconnection.
Silent Mode: Press and hold the large test button for five seconds to stop false alarms.
Interconnection Test: Only one test button is needed for weekly testing, and the rest can be tested simultaneously.
9V Battery Backup: Powered by a 120V power supply and 9V backup battery, it can provide continuous protection in the event of a power outage.