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First Alert

First Alert BRK SC-9120B Hardwired Smoke and Carbon Monoxide (CO) Detector with Battery Backup

  • Based on 4,292 reviews
Condition: New
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Availability: Only 1 left in stock, order soon!
Fulfilled by Amazon
Arrives Monday, Sep 8
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Size: 1 Pack


Features

  • plastic
  • Imported
  • Superior carbon monoxide sensor and dual ionization smoke alarm
  • Inter-connectable with BRK and First Alert hardwired smoke and carbon monoxide alarms
  • Easy to install universal mount bracket
  • Simple to use silence/test button; separate smoke and CO latching alarm indicators
  • 9-volt battery included; 10-year limited warranty
  • Faster turnarounds on job sites with the easy-to-install, most-trusted alarms in home safety

Description

This smoke and carbon monoxide detector provides 24/7 protection. It runs on 120V and has a 9V alkaline battery backup.^^Electrochemical carbon monoxide sensor more accurate than other sensing technologies single-button test/silence latching alarm indicator remembers which unit initiated an alarm silencing technology silences low-battery chirp for up to eight hours temporarily silences an unwanted nuisance alarm end-of-life signal provides audible notification of alarm replacement intelligent sensing technology fewer nuisance alarms perfect mount for easy alarm alignment dust cover^^easy installation it's never been easier, faster, or more cost-effective to install a smoke and carbon monoxide detector. A large opening in the mounting bracket provides easy access to wiring, while keyhole slots eliminate the need to remove electrical box screws for installation.^^Battery installation and removal can occur while the unit is mounted to the ceiling or wall via a side compartment. A battery pull tab keeps the battery fresh until the home is occupied. After move-in, the detector is connected to AC power with a quick connect wiring harness.^^Prevents theft it's not easy to steal this carbon monoxide and smoke detector. It includes two locking features to deter theft.^^Warranty information included with this smoke and carbon monoxide detector is a seven-year limited warranty. This warranty provides financial peace of mind should a problem ansi. This is manufactured in Mexico.

Brand: First Alert


Style: 10-year limited warranty


Power Source: Battery Powered


Color: WHITE


Product Dimensions: 2.25"D x 5.59"W x 5.69"H


Item Weight: 0.65 Pounds


Alarm: Audible


Sensor Type: Ionization


Global Trade Identification Number: 25, 69


Material: Plastic


Brand: ‎First Alert


Style: ‎10-year limited warranty


Power Source: ‎Battery Powered


Color: ‎WHITE


Product Dimensions: ‎2.25"D x 5.59"W x 5.69"H


Item Weight: ‎0.65 Pounds


Alarm: ‎Audible


Sensor Type: ‎Ionization


Global Trade Identification Number: ‎25, 69


Material: ‎Plastic


Number of Items: ‎1


Manufacturer: ‎BRK Brands


UPC: ‎000665889651 696720180278 099461840898 029054856425 029054513069


Part Number: ‎SC9120B


Item Weight: ‎10.4 ounces


Item model number: ‎SC9120B


Batteries: ‎1 9V batteries required.


Is Discontinued By Manufacturer: ‎No


Size: ‎1 Pack


Shape: ‎Round


Voltage: ‎120 Volts


Item Package Quantity: ‎1


Usage: ‎Indoor use only


Included Components: ‎First Alert SC9120B Combination Wire-In Single/Multiple Station Smoke and CO Detector 120V AC


Batteries Included?: ‎No


Batteries Required?: ‎No


Battery Cell Type: ‎Alkaline


Description Pile: ‎9V


Warranty Description: ‎10 Years Limited


Date First Available: January 1, 2008


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, Sep 8

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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Similar Products

Top Amazon Reviews

    • Replacing These Life Saving Devices Every Five Years is as Easy as Screwing in a Light Bulb!
Size: 1 Pack
About 6 years ago I had this product installed in the basement, on the main floor and upstairs in our home. I had never had a problem until last month. The alarms were hardwired and contained a 9 volt battery in case the power was to go out. The alarms woke us up in the middle of the night and terrorized us for 24 hours. I changed the batteries on all of the alarms and they worked fine for a few hours then noise began again. Frightened that we may have carbon monoxide in the house, I called an electrician. Sixty-five dollars service call and $50 for one new BRK SC9120B Smoke and Carbon Monoxide Alarm later we were fine for about three hours, then the noise kicked in again. Unable to deal with the noise, I unplugged all of the alarms. I checked local stores for replacements for the other two alarms; however, one said they did not carry this brand and the other said that they would have to special order them. Finally, I checked amazon.com. Scheduled to go away for the weekend, I ordered two BRK SC9120B Smoke and Caron Monoxide Alarms using amazon.com and amazon.com's free "Prime" shipping at a total cost of $70.00. The following Monday morning the alarms arrived. With the old brackets in place, I followed the instructions, plugged the new devices in and screwed them into the brackets. The whole process took about 10 minutes and required about the same skill as screwing a light bulb in. They work fine now. After reading the instructions included with the box, I learned that these alarms are built to last 5 years. Mine lasted 6 years. I am comforted and sleep easy with the knowledge that my devices are top of the line smoke and carbon monoxide alarms with alkaline battery back-up that will protect me and my family for at least 5 more years. I saved a total of $30 on the devices I bought from amazon.com. Now that I know an electrician is not necessary to replace these alarms in the future, I will save the cost of a house call in addition to the list price of the alarms from the electrician. These are easy to install reliable devices that save lives. Enjoy! ... show more
Reviewed in the United States on December 13, 2011 by Tom McGee
    • Satisfied
Size: 1 Pack
Easy to install. Good price point. Replaced a set that was at least 15 years old.
Reviewed in the United States on May 14, 2025 by Lisa Frazier
    • Smoke and carbon monoxide alarm replacement
Size: 1 Pack
Review Image by Ty Ty
We were quite confident in the safety of the system interaction since the new alarm types matched the existing alarms in our home. Tested it with the existing system, and no issues. The design was perfect for us and there is a clip that connects the alarm’s wiring to the home’s existing wiring that we removed and replaced with ease. ... show more
Reviewed in the United States on June 20, 2025 by Ty Ty
    • Reliable and easy to install.
Size: 1 Pack
I bought the same exact model, because the last one lasted me 11 years. Your should replace them every 10 years maximum.
Reviewed in the United States on June 11, 2025 by Jeff L
    • BRK SC9120B Hardwired
Size: 1 Pack
10/2011 Update One unit malfunctioned last night, 10/2011, which is why I am on the sight purchasing another unit and updating my review. As the units are in series it took some time to figure out which one was defective...I had to take two down, leaving the battery in until the bad one went off again to indicate it was malfunctioning. Why does it always happen at bedtime? I only give four stars on reliability for two reasons. First when I first received the four units, one was bad, so I had to return it for a replacement. Second the unit I am replacing is only 3 years old, when they are rated to last 5 years. If another unit goes early I will place them all with another brand if BRK does provide to sort of rebate. 10/2008 Originally had BRK alarms, but did research anyway as my alams were 15 years old. After doing my research decided on replacing all four of my existing alarms with this model, SC9120B. For just a few dollars more I figured it was worth having the CO2 detector on all levels of the house. Installation was simple, I replaced the connectors with the power on, NOT recommended, you need to be careful and not ground yourself, but it is much faster. The units went right in. HOWEVER one of the units was defective, it worked but did not trigger the other units to go off. After some switching of units I was able to determine which unit it was. Reqested a replacement, got it, installed it, and then returned the unit. Return was quick and easy. Some suggestions, tag the connectors in the electrical box, clearly identifing the installation date so you and others can tell when the units were installed. Before installing check the manufacture dates on the units themselves, do not accept older ones as the life of a unit is 5 years. While some people report receiving 1 to 2 year old units, mine were all only a few months old. Change the batteries once a year on a specific and rememberable date, such as the time change. The units work well, as I was leaf blowing outside this weekend and the units were triggered by the exhaust because the windows were open in the house. Turned on the whole house fan and the unit went silent after a few minutes. ... show more
Reviewed in the United States on November 17, 2008 by Flyer367
    • Perfect match
Size: 1 Pack
This is the exact match for my system. Only issue is it says last 5 years, my whole house has these and they are 9 years and work perfectly. Hope this one does the same
Reviewed in the United States on June 25, 2025 by Jody Maby
    • Peace of Mind!
Size: 1 Pack
We have a 2 year old home. One of our detectors decided to go haywire...in the middle of the night. We replaced it with this detector and allhas been quite and we have our peace of mind back.
Reviewed in the United States on July 7, 2025 by enlightenmentintexas
    • Easy to install.
Size: 2 Pack
Easy to connect
Reviewed in the United States on July 8, 2025 by Nate

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