First Alert SM210, 10-Year Sealed Battery Smoke Alarm with Slim Profile Design, 1-Pack
Original price was: $34.99.$23.98Current price is: $23.98.





Price: $34.99 - $23.98
(as of Oct 10, 2025 03:41:45 UTC – Details)
The First Alert SM210 10-Year Sealed Battery Smoke Alarm with Slim Profile Design is equipped with First Alert’s Precision Detection advance sensing technology and meets new industry standards. This slim profile smoke alarm is easy to install, and the 10-year sealed battery means no battery replacements are required.
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.
10-Year sealed battery eliminates battery replacements and low battery chirps for the life of the alarm
Slim profile design is half the depth of a standard alarm
End-of-life warning lets you know when it’s time to replace the alarm
Test/silence button for efficient testing to ensure alarm is working properly
Customers say
Customers find the smoke alarm easy to install and appreciate its 10-year sealed battery feature. However, the functionality receives mixed feedback, with some reporting it works great while others experience random false alarms. Moreover, the lifespan is concerning, with customers noting it only lasts about 18 months. Additionally, the smoke detector quality and false alarm rate receive negative feedback, with customers describing it as a poor product that gives false alarms even without cooking.
13 reviews for First Alert SM210, 10-Year Sealed Battery Smoke Alarm with Slim Profile Design, 1-Pack
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Original price was: $34.99.$23.98Current price is: $23.98.

Retired Parts Man –
looks good
as advertised
richard p. –
Awesome smoke detector
Awesome smoke detector that is very easy to install!
pld –
Lasted less than 1 year
This is the second First Alert 10 year battery sealed smoke detector I have purchased in the last three years. The first one was purchased at a hardware store and I assumed that perhaps it had been on the shelf a long time and that was why it stopped working after a year. So I bought one from Amazon thinking it would be newer, closer to the manufacturer date. I installed it on August 28, 2024. It failed on July 15, 2025. There was no fire, no smoke and nor heat indicating that it needed to go off . Thereâs no way for me to get inside it no battery replace, and it continues to chirp when I reinstall it, despite there being no smoke or heat nearby. My money was wasted. Iâve bought the old fashioned smoke detector and plan on changing the batteries when daylight savings time changes.
Amazon Customer –
Like first alert
Good smoke alarm
Stephanie Edwards Latchu –
Alarm malfunctioned after a year, First Alert is sending replacements
I’ve had these smoke detectors in my home for about a year now, and two of them started to malfunction. They started alarming (NOT chirping), in the middle of the night. One of them alarmed a few times and stopped after I took it down. The other alarmed every couple of hours until I took it down. The following night, it started to alarm again, but it was constant. I tried to silence, reset, and clean the detector, nothing would turn it off so I eventually deactivated it before I went insane.I called First Alert’s product support to let them know what was happening, and they are sending new units to my house. I am incredibly satisfied with their customer service, but wish I didn’t have to deal with the malfunctioning alarms in the first place.
Callie Estes –
Super easy to get on and off.
It definitely works well as a smoke detector. It was easy to install the base to the wall, as well as inserting the actual smoke detector onto the base. Our previous smoke detector was almost impossible to get back onto the base after silencing it and it was super annoying so we were really happy with this one. Itâs definitely loud which is what you want to smoke detector. I also appreciated the sticker on the side that had space for you to write the date that you installed it, and the date that you should uninstall it.
Alan D –
Easy install, so far, so good!
No problem with mounting, activation, and button test. Will update review in 10 years or after fire, whichever comes first!
AngDia –
Who wants to wake up to the screeching of a smoke alaram
Had to replace my smoke detector, oh yeah the middle of the night beep beep that would wake the dead. Easy installation even with having to make a new hole for the base.
Grammabub –
Well made and sturdy. Like the instructions on outer cover for use. Tested and works. Would recommend. Best one for a senior; donât have to be changing batteries all the time.
Amazon Customer –
It was easy to install and activate. Shipping was fast as well.
Jason Seniuk –
Item arrived in shrink-wrap instead of the factory clamshell, I contacted the MFG who advised that these are not sold in shrink-wrap, even when purchased in bulk. I would not trust my safety or life with something like this. Be cautious.
Catherine Hirou –
The support ring is of different size than my old detector with 9v battery. Had to make a new hole for attaching. Very simple.
Jim Corbett –
Very happy with 10 year product.