First Alert SMCO210, 10-Year Sealed Battery Combination Smoke & Carbon Monoxide Alarm with Slim Profile Design, 1-Pack

Easy to Mount and you don’t have to change the batteries. Just replace the whole thing. I prefer this over the ones you need to replace the batteries every year. One less thing to think about. I did use this one to replace an older model. It did start randomly going off, I guess that is even you know to change it. Not sure tbh

I am a 75 year young lady and found these easy to install. Excellent safety device to have in every room of your home for safety. They are compact and easy to replace. Great brightness! Highly recommended!!

If I could give these no stars I would. I purchased 2 of these in Feb to replace some old wired smoke detectors. Install was easy. The trouble came in Sept when one of them started to malfunction and give an alarm all the time when there was no smoke or heavy fumes. Nothing. Also it was not a CO alarm but a smoke. At all hours of the day and night. I finally got so sick of it that I pulled it off the ceiling and wrapped it in a blanket as my poor dog was shaking violently every time it went off. Put it back up a week later. Same problem. So I tossed it. Now here we are in Nov and the other one I bough is doing the same thing. Going off for no reason. Even wrapped in a blanket it was still going off. So I put it out on the porch. With fresh air and everything. And it continued to go off sitting outside intermittently for 2 more days before it too went in the trash. We are of course outside the return window. So I spent $80 to not have any smoke detectors in the house and will have to shell out more money again to buy another brand. These werent old. Both had been up less then 9 months when they malfunctioned. Dont waste your money on these unless you like your pets being traumatized at 2am when the thing randomly goes off for no reason and wont stop.

10 year battery

Ordered 6 of these alarms because they have the right specs, F-A rep, and are currently approved by the California State Fire Marshall. The first 4 to arrive were about 5 months old which I thought was borderline because of the 10 year legal lifespan in CA (law doesn't say time starts when you remove the plastic tab). The second two that arrived were 7 months old-nope-returned them- Amazon was great about it. Received two replacements- they were less than 2 months old- that's more like it. No false alarms yet. I didn't select 5 stars because of the poor locking into the base plate; guesstimate 5 degrees to full lock- alarm section still wiggles after rotated to lock position. This is big difference from First Alert alarms I purchased around 2013- rotates ~ 30 degrees before locking into the base. Considering that it's CA, in the event of an earthquake, I will have to remember to watch for falling smoke&CO alarms. "First Alert" packaging was great- appropriate for a life safety device.

Alarm does not work. Test worked for a month then quit. Will contact company to return.

Works as it should

I bought 5 of these when I moved into a home I bought a couple of years ago. On 3 different occasions, 3 different fire alarms had false alarms. These false alarms last 2 minutes and in my case occurred in the middle of the night. On many occasions, my wife and I would wake up in abject horror. Adrenaline dumping into our system as I jump up and try to find the source of the sound. As soon as I run downstairs it stops. I check around the house. Check the other smoke alarms, calm down and go to bed. Only to be woken up again in an hour. Finally, I figured out that these first alert alarms are the issue. The fun part is they are sealed and cant be turned off. So how do you stop them from keeping you up? No other solution but a hammer. You take it off the wall and bring it outside and break it in a million pieces. After realizing that these are garbage, I threw away 4 of them. But I forget the 5th one which was in the basement, in a room with a c02/smoke alarm from a better company. Sure enough, 2 years later, at 2:30am the piece of junk goes off for two minutes then goes silent. I just out of bed in horror, unable to find it before it stops. After the second time, i realize the sound is coming from the basement. I go down there and see that stupid first alert logo looking at me and realize that I have forgotten this last unit was year when I smashed the others two years ago. So I break out the old hammer and put it out of mine and its misery. To be clear- I have several redundant c02/smoke alarms from other companies in the house that havent gone off. So this is not a case of there being c02 or smoke that I have missed. These are just garbage. I have never written a bad review on amazon. Just this one. To say that I will never touch another first alert product in my life doesnt come close to the animosity I have for this product.