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Hero image 0 of Basic CO Alarm w/ 9V Battery, 0 of 5
Basic CO Alarm w/ 9V Battery
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.
Generated by AI
Specs
- Has nrtl listing certificationN
- Smoke & carbon monoxide alarm sensor technologyElectrochemical Sensor
- Carbon monoxide alarm typeBattery-Operated
- Power typeBattery
- Battery life5 years
- Decibel rating85 dB
Current price is USDNow $19.59
You save $6.40
was $25.99$25.99
You save$6.40
Price when purchased online
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About this item
Product details
The First Alert CO400 Carbon Monoxide Alarm utilizes a electrochemical carbon monoxide sensor that lasts for up to 5 years to detect carbon monoxide. This carbon monoxide detector is battery powered, making it portable and easy to use anywhere. When carbon monoxide levels become elevated, a loud 85dB alarm alerts you to the threat.
• Model number C0400
• Alerts to dangerous carbon monoxide levels
• Most accurate electrochemical carbon monoxide sensor technology
• Battery-operated design works almost anywhere
• Loud 85dB alarm sounds when carbon monoxide levels are elevated
• Single test/silence button for simple operation
• 5-year limited warranty
• Includes 9V battery
info:
We aim to show you accurate product information. Manufacturers, suppliers and others provide what you see here, and we have not verified it.
Specifications
Brand
First Alert
Has nrtl listing certification
N
Smoke & carbon monoxide alarm sensor technology
Electrochemical Sensor
Carbon monoxide alarm type
Battery-Operated
Warranty
Warranty information
FIVE YEARS
Warranty url
Warnings
Ingestion Hazard
This product contains a battery. Death or serious injury can occur if ingested. A swallowed battery can cause Internal Chemical Burn in as little as 2 hours. Keep new and used batteries OUT OF REACH OF CHILDREN. Seek Immediate medical attention if a battery is suspected to be swallowed or inserted inside any part of the body.
Warning Text
proposition 65 reasons:WARNING: This product can expose you to chemicals, such as Diisononyl phthalate or others listed on the product, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov,small_parts
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Customer ratings & reviews
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Showing 1-3 of 27 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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