The 2-pack First Alert carbon monoxide alarm utilizes an electrochemical carbon monoxide sensor to detect carbon monoxide. The battery-powered design of this personal carbon monoxide detector means your space can be monitored for dangerous carbon monoxide gas. Simply insert the included 9-volt battery and the carbon monoxide detector is ready to go. When CO levels become elevated, a loud 85-decibel alarm alerts you to the threat. Designed to be simple to use, the CO detector has just one button that silences or tests the unit, as well as an end-of-life timer that lets you know when it is time to replace the device.

Everyone should order these. Keep yourself and family members safe. Had carbon monoxide in my home and these save lives. Thank you wayfair.. Denise. Floral Park, NY. Wed Jul 15 2026

This First Alert carbon monoxide alarm features a 10-year built-in lithium battery for continuous monitoring during the life of the alarm, and uses an electrochemical carbon monoxide sensor and an 85-decibel alarm to alert you to CO threats. The advanced electrochemical CO sensor detects carbon monoxide leaks from multiple sources, such as faulty fuel-burning appliances, blocked chimneys, and generators running inside or too close to homes. Because CO evenly distributes itself, it's important to have a CO detector on every level and in every bedroom of your home. This easy-to-use alarm features a digital display that shows ambient temperature as well as peak CO levels. The detector's stylish design looks great on top of a dresser or table.

Perfect. Liz. Loudon, TN. Sat Feb 28 2026

Install convenient 2-in-1 protection with the First Alert SMICO110 10-Year Battery Combination Smoke & Carbon Monoxide Alarm. This combination smoke and carbon monoxide alarm meets new industry standards is easy to install, and doesn't require battery replacements for a decade. First Alert's Precision Detection advanced sensing technology complies with new industry standards to reduce cooking nuisance alarms and provides early warning in the event of a home fire emergency.

Great smoke carbon monoxide detector. Installation was easy and I appreciate that the battery lasts ten years.. Michelle. Portage, OH. Sun May 31 2026

This plug-in electrochemical explosive gas and carbon monoxide alarm features a backlit digital display, this explosive gas, and CO detector plugs into any AC outlet with no additional mounting hardware needed.

It's an alarm -it seems to work -haven't had a chance to truly try it out -which is good -so that is all I have to say about that lol. Kimberly. Boston, MA. Tue Mar 10 2026

The First Alert Carbon Monoxide Plug-In Alarm with battery backup features an electrochemical CO sensor to alert you to dangerous levels of carbon monoxide. This carbon monoxide detector plugs into any standard electrical socket to monitor CO levels in your home.

We are very happy with our recent purchase, as well as all of our past purchases. I would highly recommend Wayfair to my friends and family.. Dale. Rochester, MI. Fri Apr 10 2026

The First Alert SMI100 Battery-Operated Smoke Alarm is easy to install and features First Alert's Precision Detection advance sensing technology. The front access battery compartment makes for quick battery replacements and a low battery warning will advise when it's time to replace. Discourage unwanted removal of the battery or smoke alarm using the optional locking features. Use the convenient test/silence button on the front of the smoke alarm to check that it is operating properly and silence false alarms. An end-of-life warning will advise you when it’s time to replace because alarms don't last forever. Effortlessly install the CO400 Battery-Operated Carbon Monoxide Alarm throughout your home for reliable CO protection in minutes. Operation is simple. Test the CO alarm using the single test/silence button. The low battery warning will notify you when it's time to replace the alarm's battery, which is quick process due to the front access battery door, and an end-of-life warning will alert you when it's time to replace the alarm all together.

working good no problems easy installl. Jack. Prescott, MI. Sat Jul 25 2026