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BRK

BRK SC9120B Smoke and Carbon Monoxide Alarm

  • Based on 490 reviews
Condition: New
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Availability: Only 1 left in stock, order soon!
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Arrives Sep 15 – Sep 19
Order within 7 hours and 24 minutes
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Features

  • Superior carbon monoxide sensor and dual ionization smoke alarm
  • Simple to use silence/test button; separate smoke and CO latching alarm indicators
  • 9-volt battery included; 7-year limited warranty
  • Inter-connectable with BRK and First Alert hardwired smoke and carbon monoxide alarms
  • Easy to install universal mount bracket

Description

BRK Hardware Combination Smoke and Carbon Monoxide Alarm This unit detects two hazards in one simple device. Carbon monoxide (CO) is a colorless, odorless, deadly gas emitted by sources such as gas/oil furnaces, gas clothes dryers, water heaters, fireplaces, wood stoves, charcoal grills, gas ranges, and space heaters. Clogged chimneys, improper venting, and attached garages can also cause CO accumulation. The CPSC recommends at least one CO alarm near sleeping areas. The SC9120, now referenced under lot code SMI100-AC in later manufacturing runs, continues with the same core specifications. Features: · Quick plug-in power connector for easy installation · 120-volt AC interchangeable (max 18 compatible devices) · Interconnectable with up to 12 smoke alarms and 6 compatible devices (bells, horns, repeaters, door closers) · If one triggers, all smoke alarms in the series sound · Power indicators show which unit initiated the alarm · Ionization sensor – more effective at detecting fast-flaming fires · Microprocessor controlled to reduce nuisance alarms · Single test/silence button – silences non-threatening alarms/low battery warnings and tests functionality · Automatic internal functionality test · Latching alarm indicator – identifies which unit triggered the alarm · Separate visual/audible warnings for smoke and CO · Battery drawer lock and mounting bracket lock for tamper resistance · AC power indicator and alarm indicator light · Low battery warning "chirp" and missing battery tab · 9-volt battery backup for peace of mind during power outages

Manufacturer: ‎BRK


Part Number: ‎SC9120B


Item Weight: ‎10 ounces


Product Dimensions: ‎2.64 x 5.87 x 6.42 inches


Item model number: ‎SC9120B


Batteries: ‎1 9V batteries required.


Color: ‎White


Power Source: ‎battery-powered


Item Package Quantity: ‎1


Battery Cell Type: ‎Alkaline


Date First Available: May 10, 2011


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sep 15 – Sep 19

This item is non-returnable:

Non-returnable. Transportation of this item is subject to hazardous materials regulation

View our full returns policy here.

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Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Top Amazon Reviews


  • Good product & seller
Good product, works well, easy to change out.
Reviewed in the United States on July 24, 2026 by Amazon Customer

  • Great replacement
So far so good. Exact replacement from the one in the house that was 9 years old. It was easy to install. No issues since installing. Good value for the money
Reviewed in the United States on May 28, 2026 by Steve G

  • Be safe. Get this detector.
Great replacement for old unit. Works perfectly with other installed alarms.
Reviewed in the United States on August 11, 2026 by David Marino

  • easy replacement
good replacement with easy plug and play installation
Reviewed in the United States on August 13, 2026 by Big Al

  • Life saving function
Installation was easy. Always follow safety protocol. I received wiring with the purchase but did not need. I was already wired. Mounted to existing wiring no problem. I replaced my ten+ year old units. This unit is compatible with the older model and will sync alarm. I replaced all of mine. I had to use all the parts except the wiring. The size is the same in general. The base is a bit altered. It comes with a ten year battery. I found this purchase a value for my money. One of the pictures is the old model. ... show more
Reviewed in the United States on April 26, 2026 by Amazon Customer

  • Works well, just make sure you know you will have to replace in 3 years.
Good, but wish they didnt stop working after 3 years, they do have a lifespan...
Reviewed in the United States on August 4, 2026 by Teevan

  • Good product and good price.
I needed a smoke and co2 alarm for my house to replace a warn out one as I have BRK alarms throughout my house. I couldn’t find one until I looked on Amazon.
Reviewed in the United States on August 19, 2026 by Kim

  • Smoke and CO2 alarm
Easy to install, I replaced my old unit with this and the wiring and mounting were easy to follow. Works great
Reviewed in the United States on August 23, 2026 by Mark

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