The First Alert GCO1CN Combination Explosive Gas and Carbon Monoxide Alarm with Backlit Digital Display offers reliable detection of three common household threats: methane， propane， and carbon monoxide. Built for easy operation， this detector plugs easily into any AC outlet with no additional mounting hardware needed. A backlit display allows you to review the CO detector's readings， while a single button lets you test and mute the alarm with ease. The alarm can also be configured to work with almost any standard household remote control (not included)， so you can remotely silence nuisance alarms with the push of a button. Features battery back-up in case of power outage， battery included. Battery life varies according to use and application.