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    Hardwired Smoke Alarm with Battery Backup


    Designed to help promote household safety, the First Alert 9120B Hardwired Smoke Alarm with Battery Backup can provide a vital early warning of fire. This hardwired smoke detector uses an ionization smoke sensor to reliably detect smoke from hot, fast-flaming fires.


    • Ionization Sensor Reliably Detects Flaming Fires
    • Gasket-less for Easy Installation
    • Battery Backup for Detection During a Power Outage
    • Works in Tandem with Other First Alert Alarms
    • Ionization smoke sensor is optimal for detecting fast flaming fires.
    • Loud 85dB alarm.
    • Tamper resistant locking pins.
    • Single button silence/test.
    • 120V AC power with 9V battery backup (included) to keep alarm functioning during power outage.
    • Open mounting design for easy installation with side load battery compartment for quick replacement.
    • Interconnectable up to 18 units (12 smoke, 6 CO/heat/relay).
    • Emits T3 Pattern.
    • 10 Year Limited Warranty.
    • Product Dimensions (LxWxH): 5.6 x 1.9 x 5.6 in.
    • Product Weight: .60 lbs.


    • Diameter: 5.6"
    • Height: 2"


    General Details

    • Operating Voltage: 120V AC 60Hz w/ 9V battery backup
    • Operating Current: 0.04 amps (standby/alarm)
    • Temperature Range: 40°F (4°C) to 100°F (38°C)
    • Humidity Range: 10% to 95% relative humidity (RH)
    • Audio Alarm: 85dB at 10 feet
    • Test/Silence: Electronically simulates smoke condition, causing the unit
    • to alarm. Press and hold test/silence button.
    • Alarm Reset: Automatic when smoke clears
    • Interconnections: Up to 18 units of First Alert or BRK Smoke, CO and Heat
    • Alarms. Maximum of 12 smoke alarms. See user’s manual.
    • Smoke Sensor: Dual Ionization
    • Listing: Listed to UL217 Standard

    Indicator Lights/Sounds

    •  AC Power: Constant Green LED
    •  DC Power: Intermittent Red LED
    •  Local Alarm: Red LED flashes rapidly
    •  Remote Alarm: Red LED out.
    •  Latching Alarm: Green LED flashes 2 sec. on/2 sec. off after local alarm

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