First Alert 3V Electrochemical Digital Carbon Monoxide Alarm is designed to provide reliable and consistent monitoring of carbon monoxide levels in your home. This battery-operated alarm features advanced electrochemical sensors that accurately detect dangerous carbon monoxide threats. The easy-to-read backlit digital display allows you to quickly see both current and peak CO levels, ensuring you stay informed at all times. Powered by two replaceable AA batteries, it continues to function even during power outages, giving you peace of mind. Additional features include a silence/test button that lets you quiet the alarm and verify its operation, end-of-life alerts to notify you when it’s time to replace the detector, and a low battery signal mute that can silence the warning for up to eight hours. The easy-access battery door makes battery installation or removal quick and hassle- without needing to dismount the alarm. Model Number: 346504