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BRK SC9120B First Alert Smoke & Carbon Monoxide Alarm, Hardwired, 9V Battery

Brand: BRK
Model: SC9120B
Condition: New
Warranty: 7 Years
SKU: 90109
4.55 (7 Reviews)
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BRK SC9120B First Alert Smoke/Carbon Monoxide Alarm

Regular Price: $43.99
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$34.55 /ea

The BRK SC9120B First Alert smoke & carbon monoxide alarm is a 120V AC/DC, hardwired smoke and carbon monoxide alarm with battery backup and an 85db horn. This BRK combo smoke & carbon monoxide is designed to reduce false alarms. Capable of being interconnected with up to 18 devices (12 can be smoke alarms) its latching alarm indication recalls which unit triggered the alarm in the series. Its red LED indicator flashes rapidly. Afterwards, the BRK combo alarm stores it into memory and then flashes every two seconds. Simply put, the BRK SC9120B is state of the art smoke and carbon monoxide detection that meets new construction requirements.

Due to its two locking features, the BRK SC9120B smoke and carbon monoxide alarm locks the battery drawer and alarm to the base to prevent authorized tampering. Its ideally suited for apartments, hotels, dorms, or multi-family dwellingsThe First Alert SC9120B BRK smoke and carbon monoxide alarm eliminates the need for two separate devices; saving time and money. Its single test/silence button is combined making it extremely easy to use.

The First Alert SC9120B mounting system makes installation a cinch. It includes a gasket-less base for easy installation and ensures perfect alignment within minutes.The BRK SC9120B smoke alarm can be interconnected so if one unit senses smoke, all units alarm. Connecection to AC power is fast and easy with a quick connect wiring harness.

  • 9V Battery Backup
  • Fast Installation, Minimal Downtime
  • Indicator Lights for Power
  • Interconnectable up 18 Smoke Devices; 12 can be smoke alarms
  • Dust Cover
  • Easy Alignment of Alarm
  • End of Life Sound Notification
  • Hassle-Free Maintenance
  • Photoelectric Sensor Saves Maintenance Calls
  • Silences Unwanted False Alarm
  • Silences Low Battery Chirps For Up to 8 Hours
  • Single Silence/Test Button
  • Alarm Strength 85dB at 10 Feet
  • Dimensions: 5.58" Diameter x 1.97" H
  • Dual Ionization CO Sensor Metal Oxide
  • Humidity Range: 10% - 90% relative humidity
  • 120V AC w/ 9V battery Back-Up
  • 09 Amps
  • Dual Chamber Ionization Sensor
  • 40 degrees F to 100 degrees F Operating Temperature
  • Quick Connect Plug With 8" pigtails
  • Replaces Discontinued BRK smoke alarm models 4120, 4120B, 86RAC
  • Weighs 8.5 ounces
7 year warranty through BRK Electronics
Customer Reviews

Great CO/smoke detectors!

I love these CO and smoke detectors because they are so easy to replace. They are compatible with the ones the contractor installed when my house was new. So I don't need any tools--just untwist, slip off the wire connector and plug it into the new one. I really appreciate that BRK/First Alert has kept the same mounting bracket and wire connector after all these years. The warranty is 7 years and that is exactly when they all start to fail. Now when the first one goes, I just order a full set. They are high quality and I feel safe having them in my home.


on 03-23-2017 by Zippy

Easy to Install

This BRK was easy to install and reasonably priced.


on 01-11-2017 by Nicholas

Good Replacement source over retail box store

I purchase these wired w/battery in 2011 to replace our original ones from a new construction from 2005. Best price available at the time. Easy to replace when using the same mounting base in a wired system. Now in 7/2016 I have had (2) go bad because they continue to sound even after blowing out with air and replacing 9V battery. Same 5 year life problem when I had to replace all 6 in the house. These fire/smoke and carbon dioxide detectors have a 7 year warranty. You will need to call First Alert customer service instead of Westside and you will get free replacement with or without a slight service/handling charge which is reasonable. Better than buying new again if under warranty. Keep your purchase records and date of manufacture handy for warranty. Might be best to register new replacements them with the manufacture website. There may better or improved protection models, so due your research and method of wiring if you do it yourself. Check your building codes also and follow the instructions.


on 07-08-2016 by Larry

Life saving

Have a small house with these installed throughout. Saved our lives. Alarm sounded gave me time to get up, found the chimney shoot had closed and the gas was left on a little. Thankfully these went off.


on 04-11-2016 by LT

Good product dependable

One of the go to hardwired combo smoke/CO2 devices!


on 01-29-2016 by MMC

great product

I have installed dozens of this model with minimal problems.


on 01-15-2016 by Leon

Couldn't be easier

Ordered it. It came quickly and was a snap to install.


on 12-11-2015 by Thomas

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