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First Alert

FIRST ALERT SC9120B Corded Electric Combination Alarm with Adapter Plugs for Easy Replacement

  • Based on 366 reviews
Condition: New
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Availability: In Stock.
Fulfilled by RES, LLC
Arrives Jan 26 – Jan 28
Order within 17 hours and 8 minutes
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Style: Hardwired


Pattern Name: Alarm


Features

  • Convenient adapter plugs makes it easy to replace existing hardwired alarms without needing to rewire
  • Keep your family safe with this hardwired First Alert smoke and carbon monoxide alarm with a 10-year battery backup, which means constant monitoring for the life of the alarm, even if there's a power failure
  • Combination smoke alarm and carbon monoxide detector features electrochemical carbon monoxide sensing technology, as well as intelligent smoke sensing technology to reduce nuisance alarms
  • Indicator lights on the face of the unit display the presence of smoke or carbon monoxide, while an 85-decibel siren provides a clear, loud warning upon detection
  • Simple to use, with a single test/silence button; includes 10-year lithium battery with a locked drawer to prevent tampering
  • 10-year limited warranty; equipped with end-of-life signal, so you know when it's time to replace the unit for your safety
  • Rigorously tested to meet UL standards
  • To ensure complete protection make sure to place one carbon monoxide detector on each level of your home and in each bedroom

Description

This First Alert hardwired smoke alarm and carbon monoxide detector features an ionization smoke sensing chamber and an electrochemical carbon monoxide sensor. Installation and connection to AC power is easy with the included adapter plugs and "quick-connect" wiring harness so you can you easily replace existing hardwired alarms without needing to rewire. The 10-year battery backup allows for continued monitoring for the life of the alarm. Intelligent sensing technology is designed to reduce nuisance alarms; one button silences them if they do occur, and also tests detector functions. The latching alarm indicator automatically identifies which unit initiated the alarm, even after the conditions that set it off have subsided. And an end-of-life signal enhances your safety by letting you know when it's time to replace the unit. Connect it to compatible BRK or First Alert alarms within a single-family residence; connecting will sound all the alarms together.

Brand: First Alert


Style: Hardwired


Power Source: Corded Electric


Color: white


Product Dimensions: 0.07"D x 0.22"W x 0.22"H


Item Weight: 10.08 ounces


Alarm: Audible


Operating Humidity: 10-95% RH


Sensor Type: Electrochemical


Global Trade Identification Number: 86


Brand: ‎First Alert


Style: ‎Hardwired


Power Source: ‎Corded Electric


Color: ‎white


Product Dimensions: ‎0.07"D x 0.22"W x 0.22"H


Item Weight: ‎10.08 ounces


Alarm: ‎Audible


Operating Humidity: ‎10-95% RH


Sensor Type: ‎Electrochemical


Global Trade Identification Number: ‎86


Material: ‎Plastic


Number of Items: ‎1


Manufacturer: ‎First Alert


UPC: ‎029054018786


Part Number: ‎1039807


Item Weight: ‎10.1 ounces


Item model number: ‎SC9120B


Batteries: ‎1 Lithium Metal batteries required. (included)


Is Discontinued By Manufacturer: ‎No


Size: ‎No Size


Pattern: ‎Alarm


Item Package Quantity: ‎1


Included Components: ‎Alarm, Battery


Batteries Included?: ‎Yes


Batteries Required?: ‎Yes


Battery Cell Type: ‎Lithium Metal


Warranty Description: ‎Warranty


Date First Available: August 7, 2018


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Jan 26 – Jan 28

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews

    • First alert
Perfect replacement , easy to install, had it connected and functioning in a matter of minutes!!
Reviewed in the United States on November 9, 2024 by Donna Pollick
    • Perfect repacement
Plug and play, no problems
Reviewed in the United States on November 9, 2024 by Fred schreiber
    • Perfect fit
Perfect replacement for the old one. Plug and play that simple did not have to replace the base plate.
Reviewed in the United States on October 23, 2024 by Scott Taylor
    • Description as to what is included is not accurate!
These are the Smoke/CO detectors which were installed throughout our house when it was built. One of the detectors failed after a bit over 8 years (3-beeps-per-minute "malfunction/replace" alert) so I got this replacement. It serves my needs, but be forewarned, it does not come with what the listing says it does: 1) It came with an ordinary alkaline battery, not the 10-year Lithium battery advertised in the listing and indicated in the photos (fortunately the 10-year Lithium battery I installed in the previous detector was still good, so it's not a problem for me). 2) Other than the standard main wiring harness, it did not come with any adapters for other connectors (since my house is already wired for this detector, again, no problem for me). If either of those two issues are a problem for you, I recommend you look elsewhere and make sure you buy the version which lists those features on the product packaging itself (the box mine came in did not look anything like what is shown in the photos--it is yellow and black and did not mention either a 10-year battery (it specifically mentioned an Alkaline battery was included) or any adapter cables. Given the copyright date on the packaging was 2022, the revision date of the instruction sheet included was 12/22; the battery production date was 7/23 (expires 7/28) and, most importantly, the production date of the detector itself was November 2023, clearly this is recent production, yet doesn't match the current description. Furthermore if you either go to the "First Alert Store" on Amazon or the actual "First Alert" website, you will not find *any* version of the model SC9120 which does come with either of those features so ????? ... show more
Reviewed in the United States on February 17, 2024 by Bob
    • easy installation
The installation was easy and they are working as expected.
Reviewed in the United States on October 12, 2024 by Gary
    • Exact model I needed to replace
Works like a charm. Lowe’s or Home Depot, neither one had it in stock.
Reviewed in the United States on November 9, 2024 by Ran
    • Good quality product
Easy to install. Well made.
Reviewed in the United States on November 8, 2024 by nodrog
    • Exact fit and replacement.
Easily installed
Reviewed in the United States on October 11, 2024 by Gary Haisten

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