First Alert PC910 10-Year Photoelectric Combo Smoke & CO Alarm, Designer Series

2 in 1 Combo Smoke and Carbon Monoxide Alarm.10-Year Alarm Life.No Battery Changes for the Life of the Alarm.Photoelectric Nuisance Resistant Technology.Electrochemical Sensor.New Sleek/Thin Design.3V Lithium Power Cell Included.Power LED and Alarm Indicator.Mute/Silence Button.End of Life Signal.Versatile Mount- Wall or Ceiling.Easy Slide Mounting Bracket.10 Year Limited Warranty.Emits T3 Pattern