The Kidde PI9000 smoke alarm features a blinking LED light to show it is functioning properly. It also has a low-battery warning.
With both the photoelectric and ionization technologies in use most fires will be noticed before real damage can be done.
Power Source: 9V battery (included)
Audio Alarm: 85 dB at 10 ft
Size: 5 3/4″x 1 13/16″
Weight: 1 lb
Warranty: 10-year limited