Nest Protect alternative that will work with HE?

[erktrek]

There is this which will work for any smoke detector..

Kidde Smoke & CO detector

You don't need to replace them. Just get a single EcoLink FireFighter wireless audio detector, and mount it within 6 inches of any one of your Kidde smoke/co detectors. The Ecolink FF (costs ~$35-40) is a z-wave device that specifically detects smoke/CO alarms. It pairs to the Hubitat as a z-wave device and can be used as a trigger upon detection of smoke/CO alarm audio. Because the Kidde detectors are wirelessly interconnected, when any of them is triggered, all of them start alarming, includ…

Or if you wanted to have some tech fun - set up a homebridge/Node-RED server and you can detect events from Nest devices. Currently am testing skew temps on my thermostats and sending an alert if out of bounds. Also syncing my infloor heating pearl therms with my nest therms.