You can also check BRK ADK-12 Compatible Adapter Plug for Kidde Smoke Alarms - 12 Pack and First Alert BRK Brands 9120B Hardwired Smoke Alarm with Battery Backup 4 Pack for a better comparison at Smoke-detector.biz.

The Series alarms been designed to better and even smarter before.
These improvements reduce nuisance alarms time money.Single test/silence9V Battery indicator unit initiated Technology helps reduce the number alarmsPerfect Mount - for alarmDust Easy Installation/Maintenance - Preferred include a opening the for easy Keyhole mounting bracket eliminate need to remove the electrical installation. tab fresh the home is and removal while mounted to the or side battery Two features are provided theft and/or of the Connection to AC is made with harness. is easy and Limited.
Login to see all details