Basic CO Alarm w/ 9V Battery
Basic CO Alarm w/ 9V Battery
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First Alert

Basic CO Alarm w/ 9V Battery

4.6 stars out of 57 reviews
(4.6)|
57 ratings

Key item features

  • Model Number: Model number C0400 for easy identification and reference.
  • CO Detection: Alerts to dangerous carbon monoxide levels to ensure safety.
  • Accurate Sensor: Utilizes the most accurate electrochemical carbon monoxide sensor technology.
  • Battery Operated: Battery-operated design allows for use almost anywhere, providing portability and convenience.
  • Loud Alarm: Loud 85dB alarm sounds when carbon monoxide levels are elevated, ensuring you are alerted to the threat.
  • Simple Operation: Single test/silence button for straightforward operation and ease of use.
  • Included Battery: Comes with a 9V battery included for immediate use.
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Current price is Now $19.59
You save $6.40
was $25.99
Price when purchased online
  • Free 90-day returns
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Columbus, 43215
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Customer ratings & reviews

4.6 out of 5 stars
stars57 ratings28 reviews
How item rating is calculated
  1. 5 stars75% (43)
  2. 4 stars19% (11)
  3. 3 stars0% (0)
  4. 2 stars2% (1)
  5. 1 star4% (2)
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Showing 1-3 of 28 reviews

Dec 10, 2025
Esther
Item details
Size: 1
5 out of 5 stars review

Verified Purchase

Reliable, Mobile, Peace of mind

I like the fact that this CO detector is battery operated and mobile. I can move it around unlike the earlier version I had that was plugged into the wall socket. First Alert has proven to be a fairly reliable brand for my family's safety devices (CO detector, smoke detectors...etc.). With this battery powered CO detector I can move it closer to my cooking area that I use when our power goes out during the frequent winter storms in my area. Hence, this model is a great addition to my home safety devices and provides additional peace of mind. Stay safe.

Incentivized Review
Helpful?1LKXXYT6FR2T768590311
Aug 10, 2025
SPJ
Item details
Size: 1
5 out of 5 stars review

Verified Purchase

SAVE YOUR FAMILY'S LIFE

It is relief knowing that my family is covered by this easy to use, beautiful aesthetic to my decor, detection. First Alert carbon monoxide battery operated device will help save my family from the notoriously silent killer of all. I encourage all to get one and save your family's life. Thank you so much.

Incentivized Review
Helpful?1LKXXYT6FR2T768590311
Nov 24, 2025
Barb
Item details
Size: 1
5 out of 5 stars review

Verified Purchase

Good product

Same brand that I had before and lasted many many many years. I prefer to change the battery every year that way I remember to double check that it's working properly.

Incentivized Review
Helpful?1LKXXYT6FR2T768590311

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