Universal Security Instruments Universal Smoke Sensing (IoPhic) Battery-Operated Smoke and Fire Alarm, Model MDS300 Universal Smoke Sensing Technology Responds Quickly to Both Fast-Flaming and Slow-Smoldering Fires 9-Volt Alkaline Battery (Included) Operates the Alarm and Continues Protection in the Event of a Power Outage Responds 87-Percent Faster to Slow Smoldering Fires and Responds Quickest to Fast Flaming Fires Features a Quick Activation Pull-Tab and Front-Loading Battery Drawer for Replacement Without Removing the Alarm Comes With a 10 Year Limited Warranty