The Kidde Hardwired Smoke Detector with Battery Backup and Test-Silence Button model i12060 is an AC/DC powered ionization smoke alarm that operates on a 120V power source. In the event of a power failure the Kidde fire alarm comes equipped with a 9V battery backup. Using ionization sensing technology the wired smoke alarm detects invisible fire particles (associated with flaming fires) sooner than photoelectric alarms. Kidde strongly recommends that both ionization and photoelectric smoke alarms be installed to help ensure maximum detection of the various types of fire that can occur within the home. Designed to be easy to install this smoke detector includes a pre-stripped wiring harness with easy-off cap. The front battery door makes it simple to replace the smoke alarm s battery backup without the need to remove the alarm from the mounting bracket. Red LEDs indicate 4 modes of operation: Standby Mode - flashes every 40 seconds to indicate the smoke alarm is operating properly; Alarm Mode - alarm senses products of combustion; Alarm Memory - to indicate the alarm has been activated; and Hush Mode - silences the alarm for approximately 7 minutes. Green LED indicates AC power. UL Certified with a 10-year limited warranty.