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First Alert

Model # CO605

Internet # 202433878

Plug-In Carbon Monoxide Alarm with Battery Backup

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

$22.72 /each




Model # CO605

Internet # 202433878

The First Alert CO605 Carbon Monoxide Plug-In Alarm with Battery Backup is an easy-to-install, UL-listed alarm that combines advanced technology with a user-friendly design. Symptoms of carbon monoxide poisoning are like the flu, and you might not even know you're in danger. That's why a carbon monoxide alarm is an excellent way to protect your family. It detects the CO you can't see, smell or taste in the air. The CO605 easily plugs into any standard outlet with no additional mounting necessary. Powered a single 9-Volt replaceable battery, you will have the peace of mind that the alarm will work even during power outages. The test/silence button both silences a non-threatening alarm and low battery warning and allows you to test the unit's functionality. This alarm uses an electrochemical carbon monoxide sensor, the most accurate technology available. The electrochemical sensor continuously monitors CO levels and re-alarms in case of persisting dangerous levels. The alarm performs its own internal test as well, and re-alarms if carbon monoxide levels persist, sounding a loud 85-decibel horn. The back access battery compartment lets you change the 9-Volt battery conveniently. 7-year limited warranty. Meets UL standards.

  • 120-Volt AC plug-in with battery backup
  • Battery operated backup ensures alarm works even during power outages
  • Single button tests alarm functions and silences nuisance alarms
  • Back access battery compartment
  • Low battery warning
  • Uses an electrochemical sensor, the most accurate technology to detect carbon monoxide
  • End of alarm life timer
  • 9-Volt battery included
  • Loud 85 dB alarm
  • 7-year limited warranty
  • Meets UL2034 standard
  • America's most trusted brand in home safety

Info & Guides

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Product Depth (in.) 
Product Height (in.) 
Product Width (in.) 
Alarm Type 
Carbon Monoxide 
Alarm/Detector Features 
No Additional Features 
Battery Back-Up 
Commercial / Residential 
Commercial / Residential 
Connector/Contact Type 
Power Source 
Voltage (volts) 
Warranty / Certifications
Certifications and Listings 
1-UL Listed 


Rated 4.3 out of 5 by 10 reviewers.
Rated 5.0 out of 5.0 by Plug-In Carbon Monoxide Alarm with Battery Backup No drilling just plug in instructions very easy to follow. September 22, 2015
Rated 5.0 out of 5.0 by necessary device Carbon Monoxide devices are required in homes & offices where non-electric fuels are in use. So easy to forget about this! We've had great dependability with this model at home (husband is retired fire dept, so the research was deep) & I was happy to find it online! March 10, 2015
Rated 5.0 out of 5.0 by Excellent product--just what I wanted Very pleased with the carbon monoxide detectors. Just the quality one would expect from Home Depot. Shipping was prompt. It's always a pleasure shopping Home Depot, whether online or in the store. March 24, 2015
Rated 5.0 out of 5.0 by Nice and Easy! It was as simple as plugging it in. I bought these for my home that I just sold. No hassle and good price. June 30, 2015
Rated 5.0 out of 5.0 by Well-made product received earlier than scheduled. This product was as described and is easy to install, basically plug-and-play after installing the backup battery. Well-lit indicator shows exactly where unit is all the time, specially in the dark. January 1, 2013
Rated 3.0 out of 5.0 by Included batteries didn't work Fine once I changed the batteries - four out of the six I bought included batteries that were already low in charge. September 17, 2013
Rated 4.0 out of 5.0 by First Alert CO2 Detector As far as these devices go, this one seems to be good. The only thing I wished it had was a digital readout, but this can make you want to check it too often also. So, for the price, this one is worth the money spent. December 11, 2014
Rated 5.0 out of 5.0 by easy to install. works great! Great product. Attractive and easy to install. All you have to do is plug it in. April 29, 2014
  • 2015-11-26 T09:52:46.908-06:00
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