The Kidde i9080CA is a 9 V battery operated, single station smoke alarm. The i9080CA offers a Hush® feature that temporarily silences nuisance alarms and a safety light, powered by a separate 9 V battery, that illuminates when an alarm sounds to guide your way to safety. This smoke alarm uses ionization sensing technology Ionization sensing alarms may detect invisible fire particles (associated with fast flaming fires) sooner than photoelectric alarms. Photoelectric sensing alarms may detect visible fire particles (associated with slow smouldering fires) sooner than ionization alarms. Leading authorities recommend that both ionization and photoelectric smoke alarms be installed to help ensure maximum detection of the various types of fires that can occur within the home. Model i9080CA Power Source Two (2) 9V Batteries (included) Sensor Ionization Audio Alarm 85dB at 10ft Temperature Range 4.4˚C (40˚F) to 37.8˚C (100˚F) Humidity Range 10%-95% relative humidity, non-condensing Size 12.5 cm in diameter x 3.8 cm depth Weight 0.16 kg Interconnects No Warranty 10 year limited