Had to call the company because battery closure was very difficult to open and they said they recommended using a screw driver to help pry it open. I used one very gently so as not to break something, but it worked.

The inclusion of a 9V battery right out of the box is a thoughtful touch. It gives me peace of mind knowing that the detector is ready to go, and the added battery backup ensures continuous protection even during power outages. I tested the detector when it arrived, and everything checked out. The ease of setup and the immediate functionality straight out of the box impressed me. The clear instructions provided made the installation process a breeze. As a consumer, the First Alert brand has always been synonymous with reliability and trust. This CO detector is no exception. It reinforces my confidence in the brand, and I appreciate the commitment to delivering high-quality products that prioritize safety... at a reasonable price. The white design seamlessly blends with my home decor, making it unobtrusive. The compact size ensures it doesn't take up much space. In summary, the First Alert CO605 Carbon Monoxide Detector is a stellar product that offers peace of mind, reliability, and ease of use. I highly recommend it to anyone in need of a top-notch carbon monoxide detector. Five stars – well deserved!

I decided to purchase another monitor for my small house . It’s good to have one upstairs and another downstairs. The plugin feature is great— no ladders or tools required!

Bought this for my Mother-in-Law, last November. She said it stopped working the beginning of December of this year.

Simple and easy to use. Detector comes with battery which is mainly for backup or for use in areas without power as unit plugs into wall. Testing alarm was as easy as pushing the test button and there's a faint red light letting you know it's powered up. Overall a great value for the money. Small cost for what it does.

We recently had some maintenance performed on our natural gas fireplace and the technician suggested we install a carbon monoxide monitor near the fireplace, which is in the living room, just off the master suite. This item really fits the bill and Amazon's price was unbeatable. Hopefully, we'll never have a CO issue, but we can sleep well knowing this device will alert us to the problem!

Bought this since we are using our gas fireplace. It was very easy to use and to set up. The practice noise is loud and reliable. I was able to plug into the wall

This detector is compact & easy to use by just plugging it in to an electrical outlet great value.

I am super disappointed. the machine does not work. and I can not make it work. I am disappointed :( :( :(