Universal Security Instruments Hardwired 2-in-1 Carbon Monoxide & Natural Gas Smart Alarm with Battery Backup, Model MCN108 2-in-1 alarm provides double the protection with a single installation to protect against carbon monoxide and natural gas Features a quick activation pull-tab and a front-loading battery drawer for replacement without removing the alarm from the bracket Bracket mounts to any standard wiring junction box Suitable for houses, apartments, and mobile homes Comes with a seven-year limited warranty