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FIRST ALERT

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

    • Based on 4,095 reviews
Condition: New
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Availability: In Stock.
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Arrives May 2 – May 6
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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

Features a dual ionization smoke sensing chamber and an electrochemical carbon monoxide sensor, an 85dB horn and a “silence” feature. “Intelligent Sensing Technology” system is designed to reduce nuisance alarms. “Latching Alarm Indication” remembers which unit initiated an alarm. When interconnected in a series, the unit that triggered the alarm rapidly flashes its red LED indicator. After the alarm condition subsides, the initiating unit will store in memory or “latch” the information and begin to flash the LED indicator 2 seconds on, 2 seconds off. The “Perfect Mount” system features a gasketless base and a mounting bracket that keeps the alarm secure over a wide rotation range to allow for true alignment. Other Contractor Preferred features include a dust cover to keep alarm clean during construction, keyhole slots in the mounting bracket eliminate the need to remove the electrical box screws for installation. Two locking features are provided to prevent battery theft and/or theft of the unit. Connection to AC power is made with a “Quick- Connect” wiring harness. Installation is quick, easy and cost effective.

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: 10.4 ounces


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: ‎10.4 ounces


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 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: May 2 – May 6

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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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
    • Easy to install
Size: 2 Pack
These work great and popped right into the base that was already there. Makes me feel secure to know they are working 24/7 to make the house safe.
Reviewed in the United States on March 9, 2025 by Adele Marshall
    • Easy install
Size: 2 Pack
Worked as described & easy to install.
Reviewed in the United States on March 15, 2025 by Linda Chang
    • recommend
Size: 1 Pack
Perfect replacement.
Reviewed in the United States on April 10, 2025 by GMJ
    • Not a direct replacement for the older model
Size: 1 Pack
It’s a fine unit but it is not a direct replacement for my older model. My house was built in 2019, and 1 detector was malfunctioning si I needed this unit. I was hoping to just unplug my old one and plug this unit in. But the plugs are a different size and I had to disconnect the old one and wire up the new plug. I he to change the trim plate as well. It was easy to do, but it’s just wired that I went to the trouble to Oder this as a direct replacement. ... show more
Reviewed in the United States on February 5, 2025 by Paul Lo Verme
    • Great Dual Monitor
Size: 1 Pack
Initially, I was skeptical when I purchased this alarm. I used the product number, hoping to get the same one. This replacement is larger so I was disappointed, thinking that I had to return it. This is when my son came to my rescue. He realized we had to change the base for the new alarm to fit. I am happy with it. Definitely value for the money because an electrician quoted me a price of $175.00 to replace my old one. Seriously? I highly recommend it. ... show more
Reviewed in the United States on February 18, 2025 by Vivianna
    • Comes with battery
Size: 2 Pack
Works great. Come with battery
Reviewed in the United States on April 15, 2025 by Leo
    • Love it
Size: 1 Pack
This smoke and CO detector gives me peace of mind knowing my family is protected. It was easy to install and integrates well with our existing alarm system. The battery backup ensures it will still work in case of a power outage, which is a great feature. The alarm is loud and attention-grabbing, providing an effective warning. I feel much safer with this in my home and would highly recommend it for anyone looking to upgrade their safety system. ... show more
Reviewed in the United States on February 13, 2025 by Morgan

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