First Alert Battery Operated 10-Year Lithium Sealed Smoke Alarm-SA340CN - The Home Depot

First Alert

Model # SA340CN

Internet # 202433885

Battery Operated 10-Year Lithium Sealed Smoke Alarm

First Alert Battery Operated 10-Year Lithium Sealed Smoke Alarm

This item has been discontinued.
The Home Depot no longer carries this specific product.

$21.97 / box


Model # SA340CN

Internet # 202433885

The First Alert tamper resistant lithium battery powered alarm is proven to last at least 10 years without needing to replace power source. 10-year lithium power cells and tamper resistant design meet code regulations where required. No need to change the battery for the life of the alarm. Mute feature silences nuisance alarms from cooking smoke or shower steam. Single button also tests alarm functions. 10-year limited warranty. Meets UL standards.

  • 10-year lithium power cell lasts the life of the alarm
  • Ionization smoke sensor
  • Meets UL217 standard for smoke detectors
  • Tamper proof alarms are needed to meet local codes for rental properties
  • First Alert is America's most trusted brand in home safety

Info & Guides

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Product Depth (in.)  5.6  Product Height (in.) 
Product Width (in.)  5.6 
Alarm Sensor Type  Ionization  Alarm Type  Smoke 
Alarm/Detector Features  10-Year Battery,Tamper Resistant  Battery Back-Up  No 
Battery Power Type  Lithium Ion  Battery Size  Lithium Ion 
Commercial / Residential  Commercial / Residential  Connector/Contact Type  None 
Electrical Product Type  Smoke Detector  Included  Batteries 
Power Source  Battery  Returnable  90-Day 
Voltage (volts) 
Warranty / Certifications
Certifications and Listings  1-UL Listed 


Rated 3.7 out of 5 by 14 reviewers.
Rated 5.0 out of 5.0 by great easy to install handy to read looks reliable and dependable February 25, 2015
Rated 1.0 out of 5.0 by 22 Month Life Purchased and installed in November 2011. I received the "dead battery" beep at 2:00am a few nights ago. We've determined that the 10 year batteries did not make it as promised. Not sure if First Alert backs their products - still researching.... September 22, 2013
Rated 4.0 out of 5.0 by East to install I can't really comment on anything but the installation of this device. For the most part, the instructions were clear and eaisly understood except for the anti-tamper section. This part was for a model with different configuration, and it took me just a few minutes to figure out how the locking pins should work. Don't know yet if the battery will last, or how the device will operate over it's advertised 10 year lifespan. July 9, 2011
Rated 1.0 out of 5.0 by 6 months... then it goes off anytime Poor deal, if you take an extra long shower, turn on the shower heater, or look cross-eyed at it, it screams November 6, 2014
Rated 5.0 out of 5.0 by worked for 16 years installed mine in 1997. It just failed 2/2013. going to replace with the same one. February 19, 2013
Rated 4.0 out of 5.0 by Reliable alarm, but battery life is highly variable. I have four of these installed, and one just gave me the beep alert that the batteries had died, This, after 3 years and 2 months. The others seem to be going along fine, testing okay and still rendering loud and clear alarm signals. So I conclude that the batteries in these alarms are a lot like light bulbs - they can last a long time, or go out prematurely - and you never know. It would probably be more honest if this product was billed as an an "UP TO 10 year alarm." Still, I don't mind replacing after over three years. September 12, 2013
Rated 2.0 out of 5.0 by Questionable battery life Easy to install. Bought 3 of these in February 2014. One had a dead battery 4 months later, but the others are still going. Hopefully this one was just a fluke. June 22, 2014
Rated 5.0 out of 5.0 by Think is a good deal on this Like the fact that it has a ten year battery. It can be tricky to get the base off the alarm to mount it. It says to turn it and it will come off but mine was not so easy. Had to push in when turning and it finally came off. Great thing is don't have to worry about the battery for ten years. May 28, 2014
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