This smoke alarm is directly connected to 120 volt electric power, but also has a 9 volt battery (included) backup when there is no electric power. It is a dual ionization chamber smoke alarm. It has two LED indicators; green LED communicates electric power is on and being applied, and red LED communicates battery/alarm status. Battery lock-out feature prohibits mounting if the battery is not installed.

SPECIFICATIONS:
   120v AC, 60 Hz direct power with a 9V battery (included) backup
   Horn output: 85 decibels @ 10'
   Detection type: Dual ionization chamber
   Has two LED status indicators
   Can be interconnected with up to 11 additional compatible smoke alarms
   False or unwanted alarms can be silenced for up to 15 minutes
Manufacturer: FIREX
Manufacturer warranty: 5 years
Product questions: 800-445-8299