First Alert Explosive Gas And Carbon Monoxide Detector GC01CN The First Alert Carbon Monoxide and Explosive Gas Alarm GCO1CN can detect natural methane gas, propane gas carbon monoxide all in one powerful life saving alarm. A line cord allows for multiple mounting options high for natural gas, low for propane gas. Silencing and testing functions can be run by most household remote controls such as the ones used for the television, stereo, and VHS or DVD players, eliminating the need to reach the ceiling. A low battery alert chirps to remind you when to change the battery. Includes plugin with battery back up.