Kidde, 30CUA10, Hardwired Smoke & Carbon Monoxide Detector, 10-Year Battery Backup, Interconnectable LED Warning Light Indicators

Replaced our old garage alarm with this since the AC wiring was already there. You would think that an advantage to hardwire is that you don't have the damned thing screaming at you in the middle of the night to replace the battery, but this has a backup battery, so guess what? It's going to fail overnight! You might consider getting the Lithium battery type because the battery and sensor age out at about 10 years, so you might as well replace the whole thing, UNLESS you need to connect this to an alarm system. I tested ours with a candle wick because some smoke detectors, believe it or not, arrive incapable of detecting smoke. Go figure.

Well-designed detectors. It let me know that a wire had pulled out of the screwcap in the box. I love the 10 year battery and the fact I don't have to replace the battery periodically.

Purchased to replace smoke detectors in our house. I didn't realize they weren't working until we had a lot of smoke from cooking. It scared my that they didn't go off. They work great and I made sure to put the installed date one each one, using a sharpie marker. It was very easy to install.

The connectors are different from the ones I had before, even though they are both KIDDE brand. I hired the job done for me as the ceilings are 25' high in places. Was worth the $30/each price for what he had to go through to install. Also of note, the one nearest the toaster went off yesterday, even though these are supposed to be less sensitive to that. The alarm is placed 20 feet above the toaster and 10 feet away from it horizontally. Yes, a bit of the toast was burnt -- a tiny little sliver of it.

Installation was quick and simple—just swapped it out with our old unit, and it connected perfectly. The voice alerts are a nice touch, and it's great having both smoke and carbon monoxide detection in one device. Feels solid and reliable. Highly recommend!

I'm impressed with the quality and look of this detector. It is well designed, easy to install and with a nice slim look. The instructions are really thorough and explain in detail where to place the unit for optimal operation and specific places to avoid. I like that it sets your expectations about conditions or locations where it might not operate properly. So, put it in the right place! Other than trusting that it will actually work when I need it at least the tests and impressions are positive.

They randomly fault out. I've replaced a couple of them, and after ~3-6 months, they start randomly doing the 3-chirp fault sequence. I've cleaned it multiple times after each fault, and it'll keep beeping. I doubt that every other unit I have that is NOT this combo unit is perfectly fine, but only these have fault issues. Either the carbon monoxide detector is flaky and will trigger a fault with the slightest dust particle, or this is just a bad design all around. Not to mention if you have anything even remotely older than 2024, you'll need to redo your mounting plates as well as the wiring coupler that used to be on every unit under the sun. They've intentionally swapped the connector to a different style/entry position to force you to either rewire or buy their adapter kit. Very disappointing to say the least.

It contained everything I needed to replace an old device.