First Alert CO400 Carbon Monoxide (CO) Detector, Battery Operated Alarm, 1-Pack

I bought two of the First Alert Carbon Monoxide Detectors (model CO400), and I’m very happy with them. They were super easy to install — no outlet needed since they run on batteries. I just mounted them on the wall, and they were ready to go in minutes.I like that the battery operation means I can place them anywhere in my home without worrying about finding a plug. The alarm is loud enough to hear clearly, and the design is compact and simple.It gives me peace of mind knowing my family is protected. Overall, great value, easy setup, and reliable safety product. Highly recommend!

I purchased two packs of the pack of 2. So far so good!? Tested fine. Hope it actually works, which is why I went with a name brand. This is not the place to skimp. The C0400 carbon monoxide detector comes with a 9 volt battery. I knew I needed to replace my existing detector (they dont last forever, and need to be replaced ever so often) and I did not want the plug in style. I wanted battery operated so I could place it wherever I wanted and not be limited to available outlets. I also bought a second pack as a gift. I prefer giving practical, functional gifts, especially stuff that people tend to not want to buy, such as smoke alarms, fire extinguishers, carbon monoxide detectors. If you travel, consider a battery operated detector such as this. Dont trust that a hotel room has you covered, or someone else's house. It is small and light weight enough that it should be the thing to pack (take out battery, store separately until in room). I will likely buy an additional pack. Right now I have one on the first floor, and one outside my second floor bedroom door. I think having one in the basement and another in actual bedroom or elsewhere (spread out) would be better. Watch for sales, but if need be just buy them at any cost so you have them. I am even thinking about adding one to my winter car kit. If ever stuck in a blizzard and had to stay in my car for any length of time, having a detector will help as CO2 levels can quickly rise if running car (or if a few people are simply breathing without the window open a crack) to keep warm. Tail pipes can easily clog especially if windy. So yeh, simple thing to stay safe and alive

Great product lots of instructions easy to install

I can't believe the prices on CO detectors!!! They are unnecessarily expensive. My current unit was over 10 years old and kept throwing error codes so it was time for a replacement. I ultimately decided on this First Alert as it is the same brand I have trusted for years. The price was affordable. I cannot attest to any longevity or functionality because an emergency has not come up. The "Test" button does work as expected.

Easy to set up. This was a normal replacement (I didn’t know they wear out after 5-6 years), so I just had to insert the battery that came with it and re-hang it on the existing screws. It did come with screws, but I just used the ones from the old one.

I always pack a compact carbon monoxide detector when I travel—it’s small enough to slip into my luggage without a second thought, but the peace of mind it provides is huge. Whether I’m staying in a hotel or an Airbnb, it’s reassuring to know I have an extra layer of safety in an unfamiliar space. It’s one of those tiny items that takes up almost no room, yet feels absolutely essential once you start bringing it along.

They work well

These seem well-made, as I was looking at them after I took them out of the package, I put the batteries in and proceeded to mount it on the wall and all went well.

I purchased this alarm to install in the upstairs hallway between bedrooms. It was very easy to install and works perfectly and provides the added security I required. I was surprised and happy at how quickly the parcel arrived!

Quickly mounted to the wall and put batteries in. Tested. Made beep noises that split eardrums. Due to the battery nature of it it can mount anywhere close to the ground to detect CO quickly. I wont truly know if it works, and I hope I never need to, but appears solid.

This unit is very similar to the one we had for over 15 years. CO2 is a danger & we now feel safe again with the new alarm in place. The unit is just a simple plug in, but we did have to read up on where to put it. Placing it correctly is important so study up & get it right.

J’espère ne jamais l’entendre m’indiquer que nos vies sont en danger. Pour le reste tout sembke parfait...

Easy to set up, easy to use, literally something you have to have in your home.