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First Alert SMI100-AC, Hardwire Interconnect Smoke Alarm with Battery Backup, 3-Pack

  • Based on 5,874 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon

Arrives Wednesday, Jun 18
Order within 16 hours and 24 minutes
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Size: 3-Pack


Style: Precision Detection


Pattern Name: SMI100-AC


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
  • Through early warning interconnect, when one alarm sounds, all compatible alarms will soun
  • Battery backup provides continuous protection during power outages
  • Alarm indicator visually identifies the unit that initiated the alarm
  • Quick Connect Plug included allows for easy installation with no need to rewire

Description

The First Alert SMI100-AC Hardwire Interconnect Smoke Alarm with Battery Backup meets new industry standards utilizing First Alert's Precision Detection advance sensing technology. This hardwire smoke alarm is easy to install and replace existing alarms with no need to rewire. Plus interconnect compatible alarms to create a whole home alarm system to help provide an early warning.

Brand: FIRST ALERT


Style: Precision Detection


Power Source: Battery Powered


Color: White


Product Dimensions: 5"D x 5"W x 5"H


Item Weight: 0.61 Pounds


Alarm: Vibration


Sensor Type: Ionization


Number of Items: 3


Manufacturer: Resideo


Brand: ‎FIRST ALERT


Style: ‎Precision Detection


Power Source: ‎Battery Powered


Color: ‎White


Product Dimensions: ‎5"D x 5"W x 5"H


Item Weight: ‎0.61 Pounds


Alarm: ‎Vibration


Sensor Type: ‎Ionization


Number of Items: ‎3


Manufacturer: ‎Resideo


UPC: ‎029054022479


Item Weight: ‎9.8 ounces


Item model number: ‎SMI100-AC


Size: ‎3-Pack


Pattern: ‎SMI100-AC


Item Package Quantity: ‎1


Included Components: ‎Easy Adapter Plug, 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: Wednesday, Jun 18

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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Top Amazon Reviews


  • Exact fit & easy install
Size: 3-Pack Style: Precision Detection Pattern Name: SMI100-AC
Excellent replacement for original smoke detectors. Easy to install with clear instructions. Great price and LED indicators are a plus to see that units are working. A definite recommend
Reviewed in the United States on February 9, 2025 by Roy

  • Great Product!
Size: 6-Pack Style: Precision Detection Pattern Name: SMI100-AC
Easy installation-- work reliably. Nice to have these updated smoke alarms in the entire house.
Reviewed in the United States on February 11, 2025 by Cee Dee

  • I'm really satisfied with this smoke dictator easy to install work great
Size: 3-Pack Style: Standard Detection Pattern Name: 1039750
They price are awesome I buy 3 they install was easy and there are work perfect really recommended
Reviewed in the United States on February 4, 2025 by Hortensia Sierra

  • Good price.
Size: 12-Pack Style: Precision Detection Pattern Name: SMI100-AC
The installation of these smoke detectors was straight forward. Each one worked just fine. I would buy them again. My tiny problem was they didn’t come with screws. It’s a new build so no existing mounts. Wish I would have known to save a trip to a store when we live 30 miles from a store out in the country. But all in all a good product at a good price. ... show more
Reviewed in the United States on December 4, 2024 by Grammy2012

  • plug and play
Size: 3-Pack Style: Precision Detection Pattern Name: SMI100-AC
replaced all my 10 year old smoke detectors with this, just match/cross reference your part number located on the back of the one your replacing with the correct new one and no need to do any wire harness swap. just plug in and twist on , these look sleek and bright white , if you had to switch the wire harness out it would be so simple, ... show more
Reviewed in the United States on February 3, 2025 by TODD K

  • Easy installation
Size: 1-Pack Style: Precision Detection Pattern Name: SMI100-AC
Easy installation, perfect replacement for first alert 9120b
Reviewed in the United States on February 9, 2025 by Tata

  • Works fine as replacement
Size: 3-Pack Style: Precision Detection Pattern Name: SMI100-AC
Worked fine as a replacement for our old First Alert 9120B's.
Reviewed in the United States on December 28, 2024 by Patkinson

  • Great wired and battery backup alarm for the home
Size: 1-Pack Style: Precision Detection Pattern Name: SMI100-AC
This was installed in our home, wired in with a battery back up and we did not know they had a life to them. We started having issues with the alarms, we have 3 beeping on and off for several weeks. We tried changing the batteries, resetting etc. But every time a couple hours, days later it would start again! Most of the time during the night! How frustrating! While looking at the First Alert website we discovered that the alarms have a life to them, go figure. So off to buy a replacement to make them quit beeping! It worked for the alarm and now we have protection and quiet again! I do recommend the alarms. ... show more
Reviewed in the United States on January 20, 2025 by G&T

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