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First Alert CO400 Carbon Monoxide (CO) Detector, Battery Operated Alarm, 1-Pack

  • Based on 20,307 reviews
Condition: New
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$16.49 Why this price?
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Availability: Only 8 left in stock, order soon!
Fulfilled by Amazon

Arrives Saturday, Jun 7
Order within 10 hours and 39 minutes
Available payment plans shown during checkout

Size: Pack of 1


Pattern Name: Detector


Features

  • Keep your family safe with this easy to use, battery operated carbon monoxide alarm; Battery powered alarms provide continuous monitoring of CO levels, even if there's a power failure
  • Features an advanced electrochemical carbon monoxide sensor that accurately detects carbon monoxide levels, no matter where the detector is placed in the room.The alarm sequence should last 5-6 seconds. If it does not alarm, make sure fresh batteries are correctly installed, and test it again. If the unit still does not alarm, replace it immediately
  • A loud 85 decibel alarm sounds when CO levels reach dangerous , Battery Replaceable - Yes
  • To ensure complete protection make sure to place one on each level of your home and in each bedroom
  • 5-year limited warranty; Equipped with end of life signal chirp, so you know when its time to replace the unit for safety
  • All first alert CO alarms are rigorously tested to meet UL standards
  • First Alert has been the most trusted brand in home safety since launching the first residential smoke alarm in 1958 (Based on a First Alert Brand Trust Survey in February 2018)

Description

The First Alert CO400 carbon monoxide alarm uses an electrochemical sensor the most accurate technology available. The permanent sensor lasts up to 5 years. It is powered by a 9V replaceable battery giving you peace of mind even during power outages. The test/silence button silences the alarm and allows you to test its functionality. The unit monitors and re alarms if carbon monoxide level persist sounding a loud 85 decibel horn. No installation is required and the attractive design allows the unit to be placed anywhere you need it. It includes an optional wall mount with no outlet required. An audible and visual battery signal alerts you to replace the battery. Pull down action chart has convenient guide on what to do if an alarm sounds. 5 year limited warranty. Ul listed. Carbon monoxide (CO) is the leading cause of accidental poisoning deaths in America, yet many people don't know they are suffering from CO poisoning until its too late. Since symptoms of CO poisoning are like the flu, you might not even know you're in danger at first. That's why a carbon monoxide alarm is an excellent way to protect your family. It can detect the CO you can't see, smell or taste in the air. The First Alert CO400 carbon monoxide alarm uses an electrochemical carbon monoxide sensor-the most accurate technology available. The permanent sensor lasts up to five years. It is powered by on 9V replaceable battery giving you peace of mind even during power outages. The test/silence button both silences the alarm and allows you to test its functionality. The unit monitors and re-alarms if carbon monoxide levels persist sounding a loud 85-decibel horn. No installation is required and the attractive design allows the unit to be placed anywhere you need it. It includes an optional wall mount with no outlet required. An audible and visual low battery signal alerts you to replace the battery. Pull down action chart has convenient guide on what to do if an alarm sounds. 5 year limited warranty. UL listed. --Bree Norlander P.when('A').execute(function(A) { A.on('a:expander:toggle_description:toggle:collapse', function(data) { window.scroll(0, data.expander.$expander[0].offsetTop-100); }); }); Manufacturer Contact Information . See more

Brand: FIRST ALERT


Style: Battery Powered


Power Source: Battery Powered


Color: White


Product Dimensions: 1"D x 5"W x 3"H


Item Weight: 0.45 Pounds


Alarm: Audible


Sensor Type: Electrochemical


Global Trade Identification Number: 38, 99


Material: Multi


Item Weight: 0.45 Pounds


Item Dimensions D x W x H: 1"D x 5"W x 3"H


Sensor Type: Electrochemical


Alarm: Audible


Power Source: Battery Powered


Material Type: Multi


Color: White


Style Name: Battery Powered


UPC: 029054000699 069060209792 182682290273 151903436424 956258148943 041114528981 782386041364 801200948266 029054009166 163120715589 881110026452 809187149676 111012260006 777786600228 617407371796 806293934691 029054015938 014444869123 029054856067 732235256852 731215335549 803982897732 765042442101 012301816013 807031783977 100177483139 168141242892 634385631506 807320258872 680806798600 727558649931 115970757257 809386503712


Global Trade Identification Number: 38, 99


Manufacturer: First Alert


Brand Name: FIRST ALERT


Model Number: CO400


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, Jun 7

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


  • Replacement Product.
Size: Pack of 1 Pattern Name: Detector
This was a replacement item, after the original (over 5 years old) beeped to indicate it had to be replaced. Tested it & it’s working fine. Even fit right into the original screws, so happy that no wall repair/modification was necessary.
Reviewed in the United States on September 1, 2024 by Gerald S.

  • Great product
Size: 2 Count (Pack of 1) Pattern Name: Detector
Easy to install , good quality, durability.
Reviewed in the United States on July 26, 2024 by Amazon customer

  • good safety addition
Size: Pack of 1 Pattern Name: Detector
good value
Reviewed in the United States on September 27, 2024 by DEBRA Schnitzler

  • Very easy to put up but hard to open for battery
Size: Pack of 1 Pattern Name: Detector
I had this in my home when I moved in about 71/2 yrs ago. Had to move it to another location in a hall. I put up anchors with screws & glad this replacement was exactly the same. Only problem is I always have to open the battery casing with a screwdriver.. my last one eventually broke on the one side. But battery fit well & works. Guess it lasted a good while though. ... show more
Reviewed in the United States on August 17, 2024 by Gina B Gina B

  • Very reliable carbon monoxide detector
Size: Pack of 1 Pattern Name: Detector
This detector is small, compact, easy to test, and quite reliable. Our previous identical one lasted many years. The only difficult aspect here is the effort it takes to open the battery compartment. Still, all in all, a fine purchase.
Reviewed in the United States on June 12, 2024 by LMG

  • 3 pack
Size: Pack of 3 Pattern Name: Detector
Great deal for rentals. Good quality.
Reviewed in the United States on September 15, 2024 by Karen

  • for home, for travel, for car (add to winter car bag in case stuck in blizzard). 9 volt included
Size: 2 Count (Pack of 1) Pattern Name: Detector
I purchased two packs of the pack of 2. So far so good!? Tested fine. Hope it actually works, which is why I went with a name brand. This is not the place to skimp. The C0400 carbon monoxide detector comes with a 9 volt battery. I knew I needed to replace my existing detector (they dont last forever, and need to be replaced ever so often) and I did not want the plug in style. I wanted battery operated so I could place it wherever I wanted and not be limited to available outlets. I also bought a second pack as a gift. I prefer giving practical, functional gifts, especially stuff that people tend to not want to buy, such as smoke alarms, fire extinguishers, carbon monoxide detectors. If you travel, consider a battery operated detector such as this. Dont trust that a hotel room has you covered, or someone else's house. It is small and light weight enough that it should be the thing to pack (take out battery, store separately until in room). I will likely buy an additional pack. Right now I have one on the first floor, and one outside my second floor bedroom door. I think having one in the basement and another in actual bedroom or elsewhere (spread out) would be better. Watch for sales, but if need be just buy them at any cost so you have them. I am even thinking about adding one to my winter car kit. If ever stuck in a blizzard and had to stay in my car for any length of time, having a detector will help as CO2 levels can quickly rise if running car (or if a few people are simply breathing without the window open a crack) to keep warm. Tail pipes can easily clog especially if windy. So yeh, simple thing to stay safe and alive ... show more
Reviewed in the United States on January 13, 2023 by Precise Disarray

  • Works well
Size: Pack of 1 Pattern Name: Detector
Quality was good
Reviewed in the United States on September 24, 2024 by KA D

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