Battery Powered Smoke/Carbon Monoxide Combo Alarm, 9V Battery Powered, Electrochemical Carbon Monoxide Sensor, 2 Latching Features: Alarm Latch To Easily Identify Initiating Alarm After Alarm Condition Has Subsided, Low Battery Latch To Visually Identify Which Unit Is In Low Battery Condition, 2 Silence Features: Alarm Silence To Temporarily Silence Nuisance Alarms, Low Battery Silence To Silence Low Battery Chirp For Up To 8 Hours, Intelligent Sensing Technology Helps Reduce The Number Of Nuisance Alarms, Perfect Mount Allows For Easy Alignment Of Alarm, Dust Cover, Includes Mounting Anchors & Screws, Single Button Test, 10 Year Limited Warranty, NOTE: Please Check Your Local Building Code Requirements Before Installing This Product To Determine Compliance With Applicable Standards.