2 Pack, 9V, Battery Operated, Fire Alarm, Ideal For Detecting Fast Flaming Fires, Ionization Smoke Alarm Technology Detects Smoke As Soon It Enters The Chamber & Sounds The Siren, Single Test Button Checks The Functionality Of The Device, Slide Out Battery Drawer Allows Easy Battery Placement & Locks Into Place, 10 Year Limited Warranty, NOTE: Please Check Your Local Building Code Requirements Before Installing This Product To Determine Compliance With Applicable Standards.