Experience the next level of fire safety with the Kidde Smoke & Carbon Monoxide Detector, AA Battery Powered, LED Warning Light Indicators, 4 Pack, model 30CUDR. This smoke & CO detector has enhanced sensing technology that reduces false alarms often caused by cooking and sends fast alerts that help give your family more time to get out safely. To detect carbon monoxide an electrochemical sensor is used. This alarm offers a modern 5-inch design ideal for all living spaces such as living rooms, hallways, kitchens, & bedrooms. Comprehensively tested and designed to the latest UL standard for safety and reliability, the 5-inch combination smoke & CO alarm is powered by 2 replaceable AA alkaline batteries (included) for continual detection even during outages. Batteries should be replaced every 6 months or when the alarm sounds a low battery chirp. In addition, it’s self-testing and easy to install with the included twist-and-click mounting bracket. This Kidde combination alarm is equipped with end-of-life notifications that will beep to remind you it’s time to replace it at the of its 10-year lifespan. Meets requirements of 9th Edition UL 217, UL 2034 4th Edition, and FCC. Does not meet requirements for CSFM.