Universal Security Instruments SS-776-CAN-3 Battery-Operated Ionization Smoke and Fire Alarm, 3-Pack 3-Pack of Ionization Smoke and Fire Alarms respond quickly to fast-flaming fires to protect your family against deadly threats in the home 9-volt battery (included) operates the alarm and continues protection in the event of a power outage Features an audible low battery indicator, a chamber design to protect against contaminants and an alarm/power test button to ensure that the device is functioning properly Fast and easy to install with all mounting hardware included and no wiring required Comes with a 5 year limited warranty