BRK CO605B is a direct plug-in, 120-Volt AC single station carbon monoxide alarm specifically designed for residential and institutional applications including sleeping rooms of hospitals, hotels, motels, dormitories and other multi-family dwellings. CO605B features an electrochemical CO sensor, end of life signal and 2 silence features. The low power warning indicator will cause the alarm to chirp when the battery needs to be replaced. This detector can be plugged directly into a standard wall outlet.120-Volt AC plug-in with battery backupBattery operated backup ensures alarm works even during power outagesSingle button tests alarm functions and silences nuisance alarmsBack access battery compartmentLow battery warningUses an electrochemical sensor, the most accurate technology to detect carbon monoxideEnd of alarm life timer9-Volt battery includedLoud 85 dB alarm. Meets UL2034 standardAmerica’s most trusted brand in home safety