FA 10 Year Smoke/CO Alarm

First Alert 10 Year Smoke & Carbon Monoxide Alarm, Detects Both Carbon Monoxide & Smoke In A Single Device, It Is Designed For Hardwired Installation But Features A 10 Year Battery Back Up That Allows The Unit To Function In The Event Of A Power Outage, Carbon Monoxide Smoke Detector Can Be Connected To Other Compatible BRK Or First Alert Carbon Monoxide Smoke Detectors Within A Single Family Residence, Single Button Silences Or Tests The Unit, Hard Wired With Battery Back Up, Electrochemical/Ionization Sensor Type.