9120B Hardwired Ionization Smoke Alarm with Battery Backup

SKU: 9120B

9120B Hardwired Ionization Smoke Alarm with Battery Backup

SKU: 9120B


Designed to help promote household safety, the First Alert Hardwired Smoke Alarm with Battery Backup can provide early warning of fire. This hardwired smoke detector uses an ionization smoke sensor to reliably detect smoke from hot, fast-flaming fires.

  • 120-volt hardwired smoke alarm wires directly into your home’s electrical system
  • Ionization smoke sensor reliably detects particles from fast-flaming fires
  • Can integrate with up to 12 other First Alert or BRK hardwired smoke detectors
  • Easy-to-access battery drawer; 9-volt battery included
  • Hassle-free installation, no need to rewire


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Product Overview


Ionization Sensor Reliably Detects Flaming Fires

The First Alert Hardwired Smoke Alarm with Battery Backup comes equipped with an ionization sensor to provide the earliest possible warning of a fast-flaming fire. The sensor is optimized to detect flaming fires, such as those caused by paper, kitchen grease, and other fast-combusting materials.

Hassel-Free Easy Installation

To facilitate hassle-free installation, this fire and smoke alarm features a streamlined mounting system with a gasket-less base. The mounting bracket keeps the detector secure over a wide rotation range while maintaining perfect alignment. The ionization fire alarm also comes with a dust cover to keep the unit clean during construction. AC-powered smoke alarms must be installed in accordance with all local electrical codes.

Battery Backup for Detection During a Power Outage

This smoke alarm is designed for hardwired installation, but it also features a battery backup that helps ensure continued functionality in the event of a power outage. The smoke and fire detector comes with a 9-volt battery and features a pivoting, easy-to-access battery drawer that allows you to replace the battery without dismounting the hardwired alarm.

Works in Tandem with Other First Alert Alarms

In addition to functioning independently, this hardwired ionization smoke alarm can also integrate with up to 12 other First Alert or BRK hardwired alarms for coverage of larger spaces. This detector also integrates with up to six other compatible devices, such as bells, horns, and repeaters. If one alarm in the series is triggered, they will all sound. The fire alarm features a latching indicator to identify which unit triggered the alarm, alerting you to the area of danger.

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Product Manuals

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User Manual for 9120B Hardwired Ionization Smoke Alarm (English, Spanish)