The SMICO100-AC Interconnect Hardwired 2-in-1 Smoke and CO Alarm with Battery Backup utilizes First Alert's Precision Detection technology and meets the latest industry standards. Easily install and interconnect multiple detectors together to create an alarm system throughout your home.The SMICO100-AC Interconnect Hardwired 2-in-1 Smoke and CO Alarm with Battery Backup includes an adapter plug that allows for easy installation. This can also be used for replacing existing hardwire alarms. The 8th generation alarm is also equipped with a battery back to provide continuous protection during power outages. Help stop unwanted removal of the detector or backup battery using the optional locking features.