Amazon.com: First Alert Hardwired Heat Alarm with Battery Backup, BRK Brands HD6135FB : Everything Else
6000PLUS Optical Heat Sensor inc. VAD | Protec Fire and Security Group Ltd
Multisensor Smoke Heat Detectors - Blazequel
This heat detector in my house started beeping this morning. I tried to remove it to replace the batteries, but I have no clue what's going on in here. Is it safe