Quick question: what is this device?

I have this device in my basement entry and I am not sure if it is a siren or a carbon monoxide alarm or something else. Picture:


All I know is that it has a Honeywell brand on it.

I can’t say for certain, but it might be a glassbreak detector as well, especially since I believe security system-wired CO detectors have really only become a thing in recent years. If you take the cover off & snap a picture of the internal circuitry we might be able to identify it better.

Certainly looks like it’s tied to a security system, but as @TheCarson116 said, without seeing anything up close (model numbers or internals) it’s really hard to say.

To me, that looks like it is an AlarmNet Cellular Communicator, probably one of the LTE-X units.

It’s rare, but occasionally, alarm communicators don’t work when they’re placed directly above the alarm panel, which leads to putting them in whatever odd place that seems to get a signal. Also, oof, is that wire wrapped around a nail? I’m glad I don’t do residential work anymore.