Kidde 900-0113-02 Carbon Monoxide and Explosive Gas AlarmKidde 900-0113-02 Carbon Monoxide and Explosive Gas Alarm Features:; Protection from two threats, advanced alarm detects both carbon monoxide and explosive gas; AC plug with hide-a-way cord, allows direct or remote plug in; Digital readout of CO level; Continuous read of measured CO values from 30 to 999 PPM; Loud 85 decibel alarm, alerts you if CO or explosive gas levels become dangerous; Sleek design fits conveniently into any standard wall outlet; 9 volt battery included