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First Alert

First Alert Combination Smoke & Carbon Monoxide Alarm, Battery Operated Detector with Test & Silence Button, SMCO100, 1-Pack,White

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Condition: Used - Like New
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Availability: Only 1 left in stock, order soon!
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Arrives Thursday, Feb 5
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Size: 1-Pack


Style: Precision Detection


Pattern Name: SMCO100


Features

  • First Alert's Precision Detection advanced sensing technology complies with new industry standards to reduce cooking nuisance alarms and provides early warning in the event of a home fire emergency
  • Provides reliable 2-in-1 protection against both smoke and carbon monoxide
  • Battery-operated alarm allows for easy installation and maintenance
  • Test/silence button for efficient testing to ensure alarm is working properly
  • End-of-life warning lets you know when its time to replace the alarm

Description

The First Alert SMCO100 Battery-Operated Combination Smoke & Carbon Monoxide Alarm is equipped with First Alert's Precision Detection advanced sensing technology and meets new industry standards. This 2-in-1 smoke and carbon monoxide alarm provides reliable protection against both threats and is easy to install and maintain.

Brand: First Alert


Style: Precision Detection


Power Source: Battery Powered


Color: White


Product Dimensions: 5.6"D x 5.6"W x 1.9"H


Item Weight: 0.52 Pounds


Alarm: Smoke, CO


Sensor Type: Photoelectric


Global Trade Identification Number: 66


Number of Items: 1


Brand: ‎First Alert


Style: ‎Precision Detection


Power Source: ‎Battery Powered


Color: ‎White


Product Dimensions: ‎5.6"D x 5.6"W x 1.9"H


Item Weight: ‎0.52 Pounds


Alarm: ‎Smoke, CO


Sensor Type: ‎Photoelectric


Global Trade Identification Number: ‎66


Number of Items: ‎1


Manufacturer: ‎Resideo


UPC: ‎029054022066


Part Number: ‎1046776


Item Weight: ‎8.2 ounces


Item model number: ‎SMCO100


Batteries: ‎2 AA batteries required. (included)


Size: ‎1-Pack


Pattern: ‎SMCO100


Item Package Quantity: ‎1


Included Components: ‎AA Batteries


Batteries Included?: ‎Yes


Batteries Required?: ‎Yes


Battery Cell Type: ‎Alkaline


Warranty Description: ‎10 Years Limited


Date First Available: October 10, 2023


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Feb 5

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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  • Financing through Apple Pay
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Top Amazon Reviews

    • Buy
Size: 1-Pack Style: Standard Detection Pattern Name: SCO5CN
Excellent alarm. It was easy to install, the alerts are loud and clear, and I appreciate having both smoke and carbon monoxide detection in one unit. It feels reliable and well-made, giving some extra peace of mind. Definitely worth the purchase
Reviewed in the United States on November 17, 2025 by Aaron
    • Easy install and shower steam does not set it off
Size: 1-Pack Style: Precision Detection Pattern Name: SMCO100
So I needed a smoke and CO2 detector that would not go off every time someone showered. The steam was setting off the old one. This one is perfect and solved the problem. Also like that it takes standard batteries.
Reviewed in the United States on January 21, 2026 by TimB
    • Good product
Size: 1-Pack Style: Precision Detection Pattern Name: SMCO100
Works for us, no issues over the last few months.
Reviewed in the United States on January 22, 2026 by Kindle Customer
    • Good smoke alarm, great warranty!
Size: 1-Pack Style: Standard Detection Pattern Name: SCO5CN
Good smoke/CO detector, malfunctioned after a couple years. I called the company and given their generous warranty policy, they replaced it with the new model for free, just had to pay a few dollars for shipping.
Reviewed in the United States on June 23, 2025 by sol lazarus
    • Great price and fit!
Size: 1-Pack Style: Precision Detection Pattern Name: SMCO100
Great brand easy to install! Be mindful of the difference between just smoke and CO and smoke detectors! Other than that, excellent purchase - better price point than local hardware stores.
Reviewed in the United States on January 11, 2026 by Miguel Varela Acosta
    • Can’t go wrong with first alert. Piece of mind.
Size: 3-Pack Style: Precision Detection Pattern Name: SMCO100
A member of our family had a close call with some Co2 recently. This prompted me to get six of these first alert combo detectors. Installation is very straightforward. I now have one in every bedroom and the hallway and the kitchen. The fact that they are battery operated is a big plus. No wiring no electric electricians just two screws and you are done. I know that first alert has a stellar reputation for safety and Quality. I have already read some of the reviews of the Great customer service and warranty provide provided as well. I just installed them so I can’t give you long-term reviews, however so far so good. ... show more
Reviewed in the United States on January 4, 2026 by David McKean
    • Best safety device
Size: 3-Pack Style: Precision Detection Pattern Name: SMCO100
Work really well, just got the FMO
Reviewed in the United States on January 6, 2026 by kashif iqbal
    • Easy to install
Size: 1-Pack Style: Precision Detection Pattern Name: SMCO100
Easy to install as used same base as ones I had. The ones I am replacing were over 10 years old and was working fine. Very easy to replace the batteries(2 AA).
Reviewed in the United States on December 31, 2025 by Wayne Mitchell

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