First Alert PRC710 PC1210 10-Year Combination Carbon Monoxide and Photoelectric Smoke Detector, Frustration Free Includes Carbon Monoxide Alarm along with the Smoke/Fire Detector all-in-one unit 10-Year sealed battery means no battery replacements for 10-year life of the alarm Nuisance free photoelectric technology reduces false alarms that result from cooking and shower steam Meets UL standards & complies with legislative requirements for 10-year battery operated smoke alarms 10-year Limited Warranty