Kidde Carbon Monoxide Detector, 10-year battery backup, digital display, test/hush button. Easy Installation - simply plug-in to a standard, 120V outlet in your home 10-year lithium battery backup provides protection during a power outage Digital LED display shows the level of carbon monoxide the CO alarm is sensing 85-decibel alarm & a number of parts per million on the digital display indicates the presence of carbon monoxide Peak Level Memory records the last time carbon monoxide was detected or when the unit was last tested Test-Hush button makes it easy to test the carbon monoxide detector or temporarily silence the low battery chirp warning. 1488 4 28