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Model # SC9120B

Internet # 202433890

Hardwired Interconnected Smoke and CO Alarm with Battery Backup

This item has been discontinued.
The Home Depot no longer carries this specific product.

$33.00 /each




Model # SC9120B

Internet # 202433890

The BRK Hardwire Interconnected Ionization Smoke and Carbon Monoxide Alarm detects two life-threatening hazards in 1 simple unit. This alarm uses visual and audible warnings when triggered and can easily be silenced during false alarms by pushing the test/silence button. A 9-Volt battery backup provides reliable operation, even in power outages, and the unit chirps when the battery is running low on power.

  • Combines a smoke and carbon monoxide detector in a single unit for comprehensive protection
  • Separate visual and audible warnings for smoke and carbon monoxide detection
  • Automatically performs internal test of functionality
  • Test/silence button ceases a non-threatening alarm or low-battery warning and allows you to test the unit's operation
  • 9-Volt battery backup for peace of mind during power outages
  • Battery door lock and mounting bracket lock for tamper resistance
  • Microprocessor controlled for fewer nuisance alarms
  • Low-battery warning chirp and missing battery tab alert you when unit requires a new power source
  • AC power indicator and alarm indicator light for easy identification of alerts
  • Quick plug-in power connector for easy installation
  • Interconnect with up to 18 other compatible smoke alarms and 6 compatible devices like bells, horns, repeaters and door closers (not included)
  • Latching alarm indicator remembers which unit initiated an alarm
  • 7-year limited warranty
  • America's most trusted brand in home safety

Info & Guides

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Product Depth (in.) 
Product Height (in.) 
Product Width (in.) 
Alarm Sensor Type 
Alarm Type 
Carbon Monoxide 
Alarm/Detector Features 
Battery Back-Up 
Commercial / Residential 
Commercial / Residential 
Connector/Contact Type 
Power Source 
Voltage (volts) 
Warranty / Certifications
Certifications and Listings 
1-UL Listed 


Rated 4.2 out of 5 by 63 reviewers.
Rated 5.0 out of 5.0 by Great purchase It is two-In-one... smoke and carbon monoxide... easy to install and a great price at homedepot only! October 20, 2015
Rated 2.0 out of 5.0 by Ordered 2 - one died within a week. I had three of these installed three years ago. All are interconnected. Two went bad after a few months. Replaced both and within a week, one of the units went bad. Chirps with a brand new battery, chirps in different places in the house. Fancy product - when it works. October 13, 2015
Rated 5.0 out of 5.0 by BRK smoke and CO detector wired The BRK smoke and CO2 detector was easy to install. The entire process of installing the two detectors was less than one hour. This is another prime product by first alert October 13, 2015
Rated 5.0 out of 5.0 by Smoke and CO alarm by BRK Excellent product by BRK. This product was easy to install. Start to finish for both was less than an hour. October 13, 2015
Rated 5.0 out of 5.0 by Great purchase Replaced old alarms within 5 mins. Great quality!! November 11, 2015
Rated 5.0 out of 5.0 by Replacement smoke/CO detector The smoke detector that came with my house malfunctioned. It was a hardwire/battery back up. Rather than having to hard wire a new base into my ceiling. I purchased an identical model, on-line, and it was delivered, free, to my local Home Depot. From there, I simply unplugged the bad unit and and plugged in the new one. Mission accomplished. November 3, 2015
Rated 5.0 out of 5.0 by Good product, good value, quick delivery Installation was easy. Replaced existing smoke alarms. November 10, 2015
Rated 1.0 out of 5.0 by Don't spend your money My builder installed 3 of these in my new home two years ago. All three have gone off late at night at least four times in the last two years for no apparent reason. I've replaced the batteries, vacumed them and they still false alarmed. After removing them them from the ceiling they still went off until I removed the batteries. I'm throwing all of them out and going to by basic smoke detectors (not First Alert)for replacements and buy separate, plug-in type CO Detectors.These are too expensive to be buying every two years not to mention being woke up in the middle of the night for no reason. October 17, 2012
  • 2015-11-25 T10:37:54.567-06:00
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