First AlertCO400 Carbon Monoxide (CO) Detector, Battery Operated Alarm, 1-Pack

They are nice to set up but I didn’t like how the batteries were just running loose to where the positive and negative contacts can hit the battery just in front of it, and the battery in front has a metal bottom where the one behind it can make contact I think if both or one of them could be wrapped up so they don’t touch each other but other than that it’s a good deal

Why did you pick this product vs others?:Very nice

Simple and effective.

I'd been meaning to get one of these to go in my emergency heating and cooking kit, but I only got around to ordering it when I realized my car might still have an exhaust leak even after being "fixed" twice.Only after it arrived did I find out that this detector does not work appropriately to detect low-level exhaust leaks in vehicles. It doesn't work well for any intermittent lower-grade leak.The detector is designed to meet UL guidelines which require alarms NOT to go off until certain amounts of time have gone by. Extremely high levels of CO will trip the alarm very quickly, but lower levels won't set off the alarm for hours or days depending on the CO level. So this device (and all devices meeting the same UL standard) is useless as a low-level exhaust leak detector. I would have to run my car with sealed doors and windows for many hours or even days to satisfy the UL timelines, and even if there's an unsafe CO level, the device might not alarm if I turn my car off a half hour early. Basically the device can detect a huge range of CO levels but there's no way for you to access that info, and the alarm is unreliable for intermittent leaks.Once I figured this out, I looked into solutions. I found lots of references to low-level detectors and CO meters, but they pretty much all cost $100 or more. I don't need low level detection, just instant feedback. Thankfully you can get instant feedback on cheaper, less-sensitive devices!I should have gotten the next model up from this, one of the Kidde Nighthawks. They only cost 7-10 bucks more than this one but you can see the current and peak CO ppm on the display. If you check in on the device occasionally, you could feasibly address issues before they become life-threatening. I didn't realize how much more useful it would be to have a display, because I thought all detectors just alarmed immediately as needed.This detector is great for what it is and I'm grateful that it's so affordable, so more people can access this type of device. They cost a fortune where I live. But I think you should have at least one detector with a screen in your house!(PS: CO detectors aren't rugged enough to be left in cars--the manual says not to use this one in direct sunlight or near ventilation, which is a challenge in a car, plus the heat of a car will destroy the sensor.)

This was an exact match for the one that died, thank you! I was able to replace it without fuss, and ... 'somebody painted around the old one' so another shape would have been awkward. It's testing as it should, loud enough to terrorize 2 old terriers - but then, a chirping 'low battery' sends them scratching at the door to get out. Full alarm puts them into total gibbering panic, it's plenty loud enough! Priced right, shipping good.

Great product works as it should and gives instant peace of mind! Even comes with batteries for convenience!

All my smokies, and CO detectors are First Alert. Other brands tend to set off false alarms and are bulky. Very easy to install and test.

My second purchase of this detector. Replacing the first one that lasted 7.5 years until getting the "end of life" beeping code. I like that this let me know when to change the 9v battery. I use a 9v lithium rechargeable. I'm happy with the longevity of the detector at this reasonable cost.