Kidde Firex Mains Powered Smoke Alarm or Heat Alarm with Back-up Battery
Replacing an old Firex FX1218 hardwired smoke detector? : r/fixit
Kidde Firex Smoke Detector, Hardwired with nine-V Battery Backup & Front-Load Battery Door, Smoke Alarm, 4-Pack 21030967 - The Home Depot
Hi, I'm going to attempt to replace these Firex smoke detectors myself. can I just buy the most recent model of these and swap them out, leaving all the old wires? Or