BRK First Alert® Single station CO alarm is perfect for use in residential and institutional applications including sleeping rooms of hospitals hotels motels dormitories and other multifamily dwellings. Alarm in white color measures 4.9 Inch x 3.4 Inch x 1.6 Inch. Alarm featuring solid-state piezo horn has noise level of 85 DB at 10 ft. It incorporates electrochemical CO sensor to ensure maximum protection/safety. This alarm automatically resets when CO clears. It provides audibl