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The First Alert CO400 Carbon Monoxide Alarm utilizes an electrochemical carbon monoxide sensor that lasts for up to five years to detect carbon monoxide. This carbon monoxide detector is battery powered, making it portable and easy to use anywhere, even in the event of a power outage. When carbon monoxide levels become elevated, a loud 85-decibel alarm alerts you to the threat.
The Most Accurate CO Sensor Available
The First Alert Carbon Monoxide Alarm uses an advanced electrochemical CO sensor to detect elevated carbon monoxide levels. When CO is detected, the carbon monoxide detector sounds an alarm to warn you of the threat.
Comprehensive Warning Features
When carbon monoxide levels rise, the carbon monoxide detector sounds an 85-decibel siren that is designed to wake even the soundest of sleepers. A low-battery light and alarm alert you when battery power is running low, and an end-of-life timer lets you know when the device should be replaced. Each CO detector lasts approximately five years.
Simple and Easy to Use
The First Alert Carbon Monoxide Alarm is easy to set up. Simply insert the battery, and the CO detector will start to monitor your space for carbon monoxide. There are no complicated displays or settings to navigate. A single button silences the alarm and tests the CO detector. A pull-down action chart instructs you of what to do if the CO alarm goes off.
Where To Place Carbon Monoxide Alarms: One on every level of the home and one in each sleeping area.
First Alert Carbon Monoxide Alarm CO400
Average Rating Based on 139 reviews: (4.9)
Basic CO protection - 03/12/2019
Reviewer: Gerald Lomashewich
The low cost of this alarm lets you get a couple more and have better coverage in you house. This alarm will quickly sound if CO is detected.
Ms Nichola Frick - 03/04/2019
Reviewer: Nichola Frick
Due to the fact that I had such good luck with the first one when it stopped working I decided to purchase the same brand. I was pleasantly surprised to see you still carried the exact model. Looking forward to having good luck with this one too. Thank you Nichola Frick
Reviewer: Scott Favero
product is of good quality and well accepted by the public sector
Reviewer: Roger Schulenburg
Replaced old one. Works great
Carbon Mono Alarm - 02/28/2019
Reviewer: Patt McDermid
Prompt and efficient delivery of excellent alarm. Thanks.
Reviewer: STACEY KIRN
Happy with product and shipping. Would definitely order from you again.
Excellent product and service - 02/22/2019
Reviewer: Lorna Wright
After checking reviews online including a national consumer reporting service I chose the First Alert CO detector. The First Alert store online is very easy to use and I highly recommend that you purchase directly from them.
Good simple alarm - 02/14/2019
Reviewer: Igor Kripak
Easy installation, could save a life some day
First Alert Basic Battery Operated Carbon Monoxide Alarm - CO400 - 02/13/2019
Order process online was very easy to complete and product arrived on time.
Great Product! - 02/08/2019
Reviewer: Jane Hicks
I'm very happy with my new First Alert carbon monoxide detector. It was easy to install the battery and has easy to understand directions. I hope I never hear the alarm, but the test button, once pressed, is loud, and would certainly wake me if it does go off.
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