Combination Explosive Gas & Carbon Monoxide Alarm, With Backlit Digital Display, Versatile Carbon Monoxide Alarm Senses High Levels Of Propane, Natural/Methane Gas & Carbon Monoxide, Crisp Backlit Digital Display Allows You To View Current & Peak Levels, Can Be Remotely Muted Using Almost Any Household Remote Control, Plugs Into Any AC Outlet For Easy Set Up, Back Up Battery Powers Unit In Case Of Power Outage, Loud 85 Decibel Alarm, Electrochemical Sensor Type.