The kidde 10y29 photoelectric alarm is a state of the art optical smoke alarm designed for easy installation and a guaranteed 10 years life the optical photoelectric sensor is highly efficient at detecting slow burning and smouldering fires such as furniture the small diameter of the smoke alarm just 104mm reduces its storage space needs the kidde 10y29 alarm features an innovative early and silent low battery warning this means that rather than chirping and beeping an led light will flash at th