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First Alert

First Alert SMI100, Battery-Operated Smoke Alarm, 1-Pack

  • Based on 24,827 reviews
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Availability: In Stock.
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Arrives Saturday, Sep 13
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Size: 1-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


Power Source: Battery Powered


Color: White


Product Dimensions: 5.4"D x 5.4"W x 1.9"H


Item Weight: 0.7 Pounds


Alarm: Smoke Alarm


Sensor Type: Ionization


Number of Items: 1


Manufacturer: Resideo


Style: Precision Detection


Brand: ‎FIRST ALERT


Power Source: ‎Battery Powered


Color: ‎White


Product Dimensions: ‎5.4"D x 5.4"W x 1.9"H


Item Weight: ‎0.7 Pounds


Alarm: ‎Smoke Alarm


Sensor Type: ‎Ionization


Number of Items: ‎1


Manufacturer: ‎Resideo


Style: ‎Precision Detection


UPC: ‎029054022387


Item Weight: ‎11.2 ounces


Country of Origin: ‎Mexico


Item model number: ‎SMI100


Size: ‎1-Pack


Pattern: ‎SMI100


Item Package Quantity: ‎1


Included Components: ‎9V Alkaline Battery


Batteries Included?: ‎Yes


Batteries Required?: ‎Yes


Battery Cell Type: ‎Alkaline


Date First Available: September 22, 2023


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, Sep 13

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

    • 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
    • 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
    • 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
    • Happy camper
Size: 2-Pack Style: Precision Detection Pattern Name: SMI100
I was surprised when I started looking for replacement smoke detectors that California requires only the new 10 yer smoke detectors. I was pleased that I was able to get these less expensive models shipped to California since the reviews on the 10 year models are not all that great.
Reviewed in the United States on April 27, 2025 by The Wandering Steeles
    • Definitely recommend
Review Image by Lisa Lisa
We got a new furnace recently. The gas kicked on and burned some of the residue off the furnace from when they installed it. It tripped this smoke detector even though there wasn't even any visible smoke. I thought the room would have to be filled with smoke for this to work but no. I definitely recommend this to anyone looking to buy a smoke detector. It is very sensitive! It will save your life! ... show more
Reviewed in the United States on April 28, 2025 by Lisa Lisa
    • Liked Them So Much I Purchased More to Replace All 7 In My Home
Size: 2-Pack Style: Precision Detection Pattern Name: SMI100
Review Image by Amazon Customer Amazon Customer
These First Alert SMI100, Battery-Operated Smoke Alarm, 2-Pack are sold by: Amazon a seller that is based in: THE UNITED STATES The product is made in: MEXICO My old smoke alarms that are all interconnected/hard-wire were constantly going off, all 7 of them at the same time...so over it... Decided to try these First Alert smoke detectors that are strictly battery operated and not hardwired...I ordered a 3 pack first to see if I liked them...I liked them so much, I ordered 4 more so that now all of them are brand new and no more blasting sirens randomly in the middle of the night when I was asleep! Super easy to install, took less than 2 minutes each to pull out the old one and replace the new one. I tested them out buy using a lighter up next to one and it went off as I hoped it would! ... show more
Reviewed in the United States on March 16, 2025 by Amazon Customer Amazon Customer
    • Good product
Size: 2-Pack Style: Precision Detection Pattern Name: SMI100
Easy to install
Reviewed in the United States on May 17, 2025 by E. S
    • Good
Size: 2-Pack Style: Precision Detection Pattern Name: SMI100
Worked great
Reviewed in the United States on May 12, 2025 by Not happy

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