Slim photoelectric smoke and carbon monoxide alarm with 10-year battery helps protect homes from two potentially deadly threats by providing up to a decade of uninterrupted monitoring. Equipped with dual sensors， detects smoke from slow-burning， smoldering fires. Half as thick as a standard alarm， features a slim， contemporary design that mounts unobtrusively on a wall or ceiling. Includes a built-in 10-year lithium-ion battery provides continuous power， with no need to ever worry about changing the battery during the lifetime of the alarm.