NEW, NEVER USED, This is a new BRK CO250B Carbon Monoxide Alarm. It's battery-powered and features a 10-year CO sensor and 10-year alarm life. This alarm includes a hinged cover for easy battery replacement and a silence feature.

The alarm is listed to UL 2034 Standard and comes with a 9V alkaline battery included. It's perfect for apartments, dormitories, or hotel applications. Bought 2 different one for my camp trailer. Used other one, purchased 6 months ago.