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FIRST ALERT

First Alert SMI100, Battery-Operated Smoke Alarm, 2-Pack

  • Based on 24,746 reviews
Condition: New
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Availability: Only 1 left in stock, order soon!
Fulfilled by Amazon
Arrives Jun 20 – Jun 30
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Size: 2-Pack


Style: Precision Detection


Pattern Name: SMI100


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
  • Battery-operated alarm allows for easy installation and maintenance
  • Front access battery compartment makes for easy battery replacements
  • End-of-life warning lets you know when its time to replace the alarm
  • Test/silence button for efficient testing to ensure alarm is working properly

Description

The First Alert SMI100 Battery-Operated Smoke Alarm is equipped with First Alert's Precision Detection advanced sensing technology and meets new industry standards. This battery-operated smoke alarm is easy to install and the front access battery compartment makes for easy battery replacements.

Brand: FIRST ALERT


Style: Precision Detection


Power Source: Battery Powered


Color: White


Sensor Type: Ionization


Number of Items: 2


Manufacturer: Resideo


UPC:


Brand: ‎FIRST ALERT


Style: ‎Precision Detection


Power Source: ‎Battery Powered


Color: ‎White


Sensor Type: ‎Ionization


Number of Items: ‎2


Manufacturer: ‎Resideo


UPC: ‎029054022400


Part Number: ‎SMI100


Item Weight: ‎8.4 ounces


Product Dimensions: ‎5.6 x 5.6 x 1.9 inches


Item model number: ‎SMI100


Batteries: ‎1 9V batteries required. (included)


Size: ‎2-Pack


Pattern: ‎SMI100


Item Package Quantity: ‎1


Included Components: ‎9V Alkaline Battery


Batteries Included?: ‎Yes


Batteries Required?: ‎Yes


Battery Cell Type: ‎Zinc Carbon


Date First Available: September 21, 2023


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Jun 20 – Jun 30

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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Similar Products

Top Amazon Reviews

    • The BEST Smoke Alarm I’ve Had
Size: 2-Pack Style: Precision Detection Pattern Name: SMI100
I just replaced my Kidde wired smoke detectors with these battery operated ones. Bought 2 to begin with, and just ordered 4 more for the rest of the house. Perfect fit! So easy to install. I just had to take off the old mount, install the new mounts, pull the battery tag, test and they are up and going. I have always went with Kidde, but have noticed over the years that some of their products aren’t as good as they used to be. The last batch of Kidde smoke alarms I bought on Amazon had a 2014 date, but I bought them in 2018. My now ex put them up. Not sure why he didn’t check the date. So I only got 7 years out of them. The First Alert smoke alarms are so easy to test. Just overall a good product. ... show more
Reviewed in the United States on April 8, 2025 by Interloper
    • Uses 9 volt (included ) and has easy access battery door.
Size: 2-Pack Style: Precision Detection Pattern Name: SMI100
This detector uses a 9 volt battery (included) and has an easy access door. You can change the battery with removing the detector. These were fresh manufacture date was 14 Feb 25. Excellent price when you order the 2 pack. It is recommended that you replace a smoke detector 10 years from the date of manufacture. I was a retired insurance agent so I would have access to loss data that the insurance industry keeps track of. 20 percent of all persons killed in a house fire did not have a working smoke detector in the home at the time of the fire. So be safe replace after 10 years and test your detectors monthly. ... show more
Reviewed in the United States on April 18, 2025 by Ed
    • Works Perfectly!
Size: 1-Pack Style: Precision Detection Pattern Name: SMI100
I had to replace all of the smoke detectors in my house because they were all just old. All were hard wired except one...way up on the wall in our vaulted living room. I climbed up to replace it and found out it was not hard wired with the rest of them. I bought this to replace that one and it's super easy to mount and replace the battery when needed. I just replaced it so I obviously can't comment on battery life but it's easy to replace so I am not worried about it. Put in a screw or two to hold the base and then simply twist the detector into place and you are done and protected. ... show more
Reviewed in the United States on January 20, 2025 by BPalmer
    • They were very easy to install
Size: 1-Pack Style: Standard Detection Pattern Name: SA320FF
Update 8/19/20: I managed to get more than two years out of the replacement, but here I am again, having bought two more. They work fine (alarm when I overcook dinner, haha), but have very early failures. The one in the living room failed again in the middle of the night. Then a few days ago our toddler closed the door to the bedroom (can't be slammed, old house, and it barely closes) and the alarm started going off. Even changing the batteries didn't help. So we've again had to replace both detectors on the main level of our house. These fit right into the old holders, which was nice. We will be moving within the next year, and I *won't* be buying these for the new house. Original review: I selected this unit when I bought a house two years ago. They were very easy to install, simply by using two screws to attach a baseplate, and then twisting on the detector. I never had them go off through any sort of false alarm (such as a steamy shower) but one too-done dinner (and the associated smoke) did trigger it. Why not 5 stars? Well, after 23 months, one of the units had a critical failure in the middle of the night. I woke up to a weird sound, and first had to locate the source. Then I had to Google it, because it was clearly not the low battery sound. It turned out to be a failure, which seemed disappointing after less than 2 years. I bought a new one because I could use the same mounting bracket (aka laziness). But if it fails again in less than two years, I won't be buying this same brand again. ... show more
Reviewed in the United States on February 15, 2016 by kdea473
    • Great Product.
Size: 2-Pack Style: Precision Detection Pattern Name: SMI100
I have been a fan of this brand for many years. I feel safe at night with all six of them standing guard. I replace all my smoke detectors every 5 years because you never know.
Reviewed in the United States on April 2, 2025 by Bill
    • Great value
Size: 3-Pack Style: Precision Detection Pattern Name: SMI100
Easy to install
Reviewed in the United States on April 28, 2025 by Ryan Dayton
    • Unit died after 6 years, but great customer service/warranty, getting replaced
Size: 1-Pack Style: Standard Detection Pattern Name: SA3210FF
5 stars for customer service. Bought 4 of these a little over 6 years ago, one started giving the end-of-life alert. Called to see if the 10-year warranty covered it, it does, they're sending a new one, no hassle. As far as the unit itself - I haven't had a fire, so that's good. A few false alarms, but only when I'm generating smoke cooking, so understandable. ... show more
Reviewed in the United States on May 1, 2025 by desert_rnr
    • Pleased
Size: 1-Pack Style: Precision Detection Pattern Name: SMI100
Good product
Reviewed in the United States on April 29, 2025 by Lynne

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